The presence of Belarusian forces near the border with Ukraine is likely to tie up Ukrainian troops so they are unable to support operations in Donbas, British defense officials said Monday.

Belarus’s military said last week it will deploy special operations troops near its southern border with Ukraine, after earlier launching large-scale drills to test the readiness of its armed forces to respond quickly to “possible crises” and counter threats from the air and ground.

Belarusian President Alexander Lukashenko, a close ally of Russian President Vladimir Putin, allowed Russian troops to assemble and conduct military drills in the Eastern European country in the run-up to Moscow’s invasion of Ukraine on Feb. 24.

A large part of Russia’s invasion force crossed into Ukraine from Belarus, which borders Ukraine to its south, Poland to its west, Lithuania and Latvia to its northwest and Russia to its east. Russia has also launched air sorties and missile strikes from Belarus, the British Defense Ministry said early Monday, although Belarusian forces so far “have not been directly involved in the conflict.”

Britain’s Defense Ministry said Lukashenko “is likely balancing support for Russia’s invasion with a desire to avoid direct military participation with the risk of Western sanctions, Ukrainian retaliation and possible dissatisfaction in the Belarusian military.”

Belarusians who oppose Lukashenko’s 28-year rule have joined the battle against Russian troops in Ukraine, The Washington Post previously reported.

Andrew Jeong contributed to this report.

The Republican U.S. senators who met with Ukrainian President Volodymyr Zelensky over the weekend also visited Helsinki as Finland take steps toward membership in NATO over fears of Russian aggression.

Senate Minority Leader Mitch McConnell (Ky.) was joined by Sens. Susan Collins (Maine), John Barrasso (Wyo.) and John Cornyn (Texas) on the surprise overseas trip. The Senate is poised to vote Monday to advance a $40 billion aid bill for Ukraine, with a final vote coming as soon as Wednesday.

Finnish President Sauli Niinisto tweeted a photo with the senators and wrote that he was “grateful” to have their support for his country’s admission to NATO.

McConnell affirmed his support, telling reporters that Finland and Sweden “will be important additions to NATO, if they choose to join.”

“I think the United States ought to be first in line to ratify the treaty for both these countries to join,” he said.

Cornyn tweeted his support early Monday, writing that Finland’s accession “will have the biggest impact on Russia, serving to double the size of Russia’s land border with NATO and entirely encircle its three ports on the Baltic Sea.”

Ukrainian folk-rap group Kalush Orchestra plans to put its Eurovision statuette up for auction, with the proceeds going toward a charity fund to support Ukraine and its military.

The band’s victory over the weekend, which gives Ukraine the right to host the hugely popular spectacle in 2023, was secured by audience votes and cheered by world leaders, in a sign of the strong public support for Ukraine as the war with Russia approaches the three-month mark.

“Many people are already donating from abroad, and perhaps many more would like to donate. And this, in our opinion, will be the thing that motivates them,” frontman Oleh Psiuk said during a Zoom call with local media after the win.

Psiuk has said the song “Stefania” was written for his mother before the war, but the band posted a music video on Sunday that features scenes of destruction filmed near Kyiv, repurposing it into a sort of tribute to Ukrainian forces. It is the latest example of Ukraine’s use of cultural diplomacy during the conflict with Russia.

Psiuk and his bandmates received special permission to travel to Italy for the Eurovision Song Contest; Ukraine has banned most men between the ages of 18 and 60 from leaving the country in case they are called to fight.

The band’s frontman was photographed Sunday kissing his girlfriend outside a Turin hotel before returning to Ukraine, where he helps run a volunteer group providing food, accommodation and medicine to people displaced by the conflict.

Russia’s invasion of Ukraine has not worked out as planned, according to NATO Secretary General Jens Stoltenberg, who argued Sunday that the war is uniting the West and could lead to NATO’s expansion — the opposite of what Russian President Vladimir Putin intended.

Stoltenberg was speaking remotely at a news conference with German Foreign Minister Annalena Baerbock. His comments followed a meeting of NATO foreign ministers to discuss the steps Finland and Sweden have taken in recent days toward applying for membership in the defense alliance.

“Russia’s war in Ukraine is not going as Moscow had planned,” the NATO chief said.

“They failed to take Kyiv. They are pulling back from around Kharkiv. Their major offensive in the Donbas has stalled,” he said.

Putin hoped a war would defeat Ukraine, weaken NATO — whose eastward expansion he views as a threat to Russia’s security — and divide Europe and North America, Stoltenberg said. “But Ukraine stands. NATO is stronger than ever. Europe and North America are solidly united.”

Stoltenberg said NATO members would continue to support Ukraine’s war effort and “make important decisions” as a group at an upcoming summit in Madrid, including on how “to reinforce NATO’s deterrence and defense to reflect the new security reality in Europe.”

Ukrainian President Volodymyr Zelensky said he will address “leading American universities” Monday and speak to Stanford University this month.

The Association of American Universities (AAU) — which includes 63 schools in the United States and two in Canada — is hosting Zelensky for a talk Monday on the “future of Ukrainian higher education.” Zelensky said in a video address Sunday that he also plans to speak with Ukrainian university students.

Ari Chasnoff, a spokesman for Stanford’s Freeman Spogli Institute for International Studies, confirmed in an email that Zelensky is set to address “the Stanford community” by video on May 27.

Finland on Monday is expected to submit a report to Parliament regarding its accession to NATO, while Sweden’s parliament and cabinet are also set to convene to discuss its desire to join the alliance.

Should the two countries formally seek acceptance into the group, as both have indicated they will, it would mark an abandonment of years of combat neutrality, spurred by Russia’s invasion of Ukraine.

Finland’s eastern border runs against Russia, and Sweden is sandwiched between Finland and NATO-member Norway, whose northernmost point touches Russia.

Among the justifications for his invasion of Ukraine, Russian President Vladimir Putin cited the possibility of a NATO expansion, which he perceives as a threat toward Moscow. The war, however, has brought the alliance closer to his door.

NATO Secretary General Jens Stoltenberg said the addition of Finland and Sweden to the alliance would be a “turning point for security” in Europe.

“Their membership in NATO would increase our shared security, demonstrate that NATO’s door is open, and that aggression does not pay,” he said.

Still, the accession is not guaranteed. All NATO countries must agree on new members, and Turkish President Recep Tayyip Erdogan has criticized Finland and Sweden over what he describes as their inappropriate harboring of “terrorists” — a reference mainly to the Kurdistan Workers’ Party, a militant organization known as the PKK, and other groups deemed so by Ankara.

Turkey became a NATO member in 1952.

Ukrainian troops appear to have forced a Russian withdrawal in Kharkiv and are launching counterattacks near the northeastern city with the aim of disrupting supply lines and making it harder for Moscow to encircle Kyiv’s forces and capture the entire Donbas region, analysts and local officials say. In the southeast, the two sides are effectively in a stalemate.

Here are updates from key battlegrounds:

Kharkiv: Ukrainian forces have mounted a counterattack in the area, pushing away Russian troops, officials say. Moscow’s forces are trying to stave off Ukrainian troops’ drive toward the Russian border, Ukrainian military officials said Sunday.

Odessa: Russian airstrikes hit tourist infrastructure and buildings in the Odessa region, its military administration said Monday.

Mariupol: The Ukrainian military on Sunday described “massive artillery and airstrikes” at Azovstal, where the last holdouts from the Ukrainian military have sheltered. Ukrainian officials say they are negotiating with Russians to release wounded fighters.

Luhansk: Ukrainian forces blew up railway bridges between the cities of Rubizne and Severodonetsk to halt Russian advances in the area, Ukrainian military officials said Sunday.

Zaporizhzhia: In this southeastern region, the front lines have almost completely frozen — with both sides effectively in stalemate, a Pentagon intelligence official said last week. From their bases in the region’s small villages, Ukrainian and Russian soldiers can barely see one another and trade artillery fire to suppress any advances.

Kyiv: A wartime curfew began an hour later starting Sunday, as the capital treads cautiously toward some semblance of normalcy. The new curfew is from 11 p.m. to 5 a.m., the mayor, Vitali Klitschko, said in a Telegram post.

Lviv: A Russian missile struck military infrastructure in this city in western Ukraine early on Sunday, regional governor Maksym Kozytskyy said in a message on Telegram. No deaths or injuries were immediately reported from the attack, he said.

Hannah Knowles and Louisa Loveluck contributed to this report.

POLTAVKA, Ukraine — There was an air of levity on the firing range as Ukrainian Territorial Defense soldiers took their first breather from the war in weeks. One by one, they took a knee to test their rocket-propelled grenades as watching comrades cracked jokes. Others turned their faces to the sun and enjoyed a moment of calm between explosions.

“You guys don’t have long before you get back out there,” a commander reminded the group. “Rest while you can.”

Almost three months into Russia’s invasion of Ukraine, Moscow’s forces are stalled in eastern regions that President Vladimir Putin promised to “liberate.” In Donbas, which Russia no longer recognizes as part of Ukraine, Moscow’s gains have been limited. To the west near Kharkiv, it has lost territory. Here in the southeastern region of Zaporizhzhia, the front lines have almost completely frozen.

Moscow’s forces are trying to stave off Ukrainian troops’ advance toward the Russian border and continuing attacks elsewhere in the east, Ukrainian military officials said Sunday.

“In the Kharkiv direction, [the Russian] enemy focused its main efforts on maintaining the occupied positions and preventing the advance of our troops to the State Border of Ukraine,” the General Staff of the Armed Forces of Ukraine wrote in a Facebook post Sunday. Kharkiv is Ukraine’s second-largest city and an early Russian target given its location near the northeastern border.

The military also said Russian forces are attacking and seeking “full control” in Donetsk and Luhansk — two eastern regions with pro-Russian separatists — as well as the region around Kherson, the southern city that Russia captured early in its invasion.

The Ukrainian military also reported Russian shelling in the Kharkiv area, while Ukrainian President Volodymyr Zelensky said in a video address that Russian missiles hit the western Lviv region as well as cities in the east.

In the southern port city of Mariupol, Zelensky said, Ukrainians “continue very complicated and delicate negotiations to save our people.” Civilians were recently evacuated from a steel plant where Ukrainian soldiers remain isolated and under assault, officials say. The Ukrainian military on Sunday described “massive artillery and airstrikes” at the plant.