Russia-Ukraine updates: Russian missiles hit close to nuclear reactors: IAEA director

Ukrainian first lady Olena Zelenska will meet with first lady Jill Biden in Washington, D.C., on Tuesday, Biden's office said, one day before Zelenska addresses Congress.

Ukrainian first lady Olena Zelenska will make remarks Wednesday before members of Congress on Capitol Hill, House Speaker Nancy Pelosi announced.

All members of the House and Senate are invited to the event, which is set for 11 a.m ET.

Russian Defense Minister Sergei Shoigu has visited the East group of Russian forces involved in the fighting in Ukraine and ordered his troops to eliminate the Ukrainian army's long-range missiles and artillery ammunition it uses to shell targets in the Donbas region, the Russian Defense Ministry said on Monday.

Shoigu instructed the group's commander to give priority to the use of precision-guided weapons to destroy Ukraine's long-range missile and artillery assets, the ministry added. Russia has accused Ukraine of using its long-range weapons to shell residential neighborhoods in Donbas communities and set fire to wheat fields and grain storage facilities.

Ukrainian officials said Russian missiles struck targets across much of eastern Ukraine on Sunday and early Monday.

Six people were killed in the town of Toretsk in the Donetsk region after Russian shelling, the state emergency service said. Missiles also struck civilian infrastructure, including a school in the Dnipropetrovsk and Odesa regions.

Russia also carried out 55 strikes on the Sumy region on Sunday. Around 60 projectiles landed in Nikopol, a dozen residential buildings were damaged and one elderly woman was wounded, local officials said.

The southern city of Mykolaiv was subjected to a massive missile strike in the early hours of Sunday as 10 missiles, presumably launched by an S-300 system, hit various parts of town.

Russian officials said on Monday that no clear timeframes have been set for the war in Ukraine, and priority should be given to its efficiency.

"We have no doubts that the special military operation will be completed after all of its objectives are attained. There are no clear timeframes, what counts most is this operation's efficiency," Russian presidential press secretary Dmitry Peskov said as quoted by Russian media.

Officials from the self-proclaimed Donetsk People's Republic claimed on Monday that DPR territory will be liberated from the Ukrainian military this year.

“The liberation of Donbas will be completed this year,” Eduard Basurin, deputy head of the police department of the DPR, said according to Russian media.

-ABC News' Edward Szekeres, Yulia Drozd, and Max Uzol

Ukrainian President Volodymyr Zelenskyy said the former head of the Security Service of Ukraine, or SBU, in Crimea, who was dismissed in the beginning of the Russian invasion, has been notified he is being charged with treason.

"Everyone who together with him was part of a criminal group that worked in the interests of the Russian Federation will also be held accountable," Zelenskyy said during his evening address Sunday. "It is about the transfer of secret information to the enemy and other facts of cooperation with the Russian special services."

A number of Ukrainian public officials have been notified they will be charged for treason and for collaborating with Russia.

-ABC News' Christine Theodorou