Ukraine’s national nuclear regulator told the International Atomic Energy Agency on Monday that a new nuclear research facility producing radioisotopes for medical and industrial applications had been damaged by shelling in the city of Kharkiv on Sunday.

The incident did not cause any increase in radiation levels at the site.

The nuclear material in the facility is always subcritical, the IAEA said, and the inventory of radioactive material is very low, so the damage reported would not have any radiological consequence.

Eight of Ukraine’s 15 reactors are currently operating, the IAEA said, citing Ukraine’s nuclear regulator.

IAEA Director General Grossi noted there have been several episodes compromising safety at Ukraine’s nuclear sites, including a recent fire at the Zaporizhzhya Nuclear Power Plant, where two reactors are still operational.

-ABC News’ Christine Theodorou

Ukraine and Russia’s foreign ministers have agreed to meet on the sidelines of a diplomatic forum in Turkey on Thursday in what will be the highest level direct meeting between the two sides since Russia’s invasion.

The meeting was agreed following a call between Turkish President Recep Tayyip Erdogan and Russian President Vladimir Putin on Sunday.

Russia’s foreign ministry spokesperson Maria Zakharova earlier confirmed the two had agreed to a meeting. Ukraine’s foreign minister Dmytro Kuleba has also confirmed it.

It’s not clear that there is much the two will be able to agree on, but it still signals a readiness by Russia to talk. For now, Russia is continuing to put forward hardline demands that Ukraine guarantee it will never join NATO or the European Union.

-ABC News’ Patrick Reevell

Russia's military has announced another temporary cease-fire in Ukraine beginning Tuesday at 10 a.m. local time and said it is prepared to open humanitarian corridors from Kyiv and several other key Ukrainian cities it has encircled.

In a statement, the Russian Ministry of Defense said the corridors would allow people to go north to Russia and its ally Belarus, adding that it would also allow routes in some places to other parts of Ukraine.

The ministry said there will be corridors from Kyiv, as well as the northern cities Chernihiv and Sumy and the key eastern cities Kharkiv and Mariupol.

Russia had initially proposed corridors only to Russia and Belarus, which Ukraine had rejected as "immoral."

However, Russia has previously violated its own cease-fire, shelling evacuation areas, and it is unclear if corridors for people to move within Ukraine will actually be made available.

Russian President Vladimir Putin also said in a video address that Russia will not call up additional reservists or send in conscripts to fight the war in Ukraine, saying it will be fought only by professional soldiers.

"The tasks are solved only by professional military personnel," Putin said. "I am sure they will reliably ensure security and peace for the people of Russia."

His comments came in a video message to Russia's women on International Women's Day, saying he understood the concerns of the "mothers, wives, sisters, brides and girlfriends of our soldiers and officers who are now in battle, defending Russia during a special military operation."

Some reports indicate that Russian conscripts have been pressured into signing professional contracts before being deployed into Ukraine.

-ABC News' Patrick Reevell

The U.N. Security Council met again this afternoon to discuss Russia’s war against Ukraine and the growing humanitarian crisis.

U.N. relief chief Martin Griffiths briefed the council, warning that U.N. agencies are being overwhelmed.

“Make no mistake. We are unable to meet the needs of civilians today,” Griffiths said. “We’re failing to meet the needs of civilians today at this time. I hope we will not fail them tomorrow.”

President Joe Biden’s envoy to the U.N. Linda Thomas-Greenfield said in the meeting that 100 Ukrainian refugees cross into Poland every minute.

Griffiths urged both sides to take “constant care to spare civilians and civilian homes and infrastructure,” including safe passage for civilians to leave war zones and allow aid to come in. He also said the U.N. was working with Russia to set up a humanitarian notification system to ensure aid can be delivered safely and at scale.

“Simply put, millions of lives shattered. People can’t stay home with shops shut, power and water cut, shells falling, phones switched off. They can’t find what they need, even if they have money to pay for it. And as we have seen, even as the TV cameras roll, many can’t flee in safety either in this conflict,” he said. “It’s been 11 days of escalating violence, fear, and pain.”

-ABC News’ Conor Finnegan

The Russian forces charging toward Kyiv haven't made progress in the last day as they face Ukrainian resistance and low food and gas supply, a senior U.S. defense official told reporters Tuesday.

However, it could be a deliberate pause, the official said. "Part of the stall could be ... as a result of their own self-determined sort of pause in operations -- that they are possibly regrouping, rethinking, reevaluating," the official said.

The U.S. believes Russian forces "have committed now more than 80% of what was their pre-staged combat power," the official added.

The official said some Russian soldiers weren't told they were going into combat. The official said "not all of them were apparently fully trained and prepared."

The strong Ukrainian resistance has also hurt morale, according to the official.

Russia has now launched more than 400 missiles on Ukraine, the official said. The U.S. believes Russia has launchers that could be used for thermobaric weapons, but cannot confirm their use, the official said.

Russian forces are making the most progress in the south. Russians are attacking Kherson in south Ukraine, which "appears very much to be contested city at this point," the official said.

Russians are also approaching Mariupol in southeastern Ukraine, and while they haven't yet entered the city, "they are close enough now that they could attack Mariupol with long range fires," the official said.

Two towns on the path to Mariupol are believed to be occupied by the Russians, according to the official.

The U.S. believes the Russians hope to move north out of Mariupol up to the heavily-contested city of Kharkiv. The official said they believe Russian forces are trying to encircle Kharkiv.

The U.S. official noted that they've seen "certain risk-averse behavior by the Russian military" over the last week.

"Take the amphibious assault, for instance. They put those troops ashore a good 70 kilometers away from Mariupol because they knew Mariupol was going to be defended and they could put them ashore in an uncontested environment. And they still haven't reached Mariupol," the official said.

"They are not necessarily willing to take high risks with their own aircraft and their own pilots," the official said.

"And of course we're seeing that on the ground -- the fairly slow and steady progress that they have made, and you guys are seeing it for yourselves on the ground where ... units are surrendering, sometimes without a fight."

-ABC News' Matt Seyler