Russia claimed Wednesday that the United States isn't interested in the rapid progress of negotiations between Russia and Ukraine.

During a speech to students at the Moscow State Institute of International Relations in Russia's capital, Russian Foreign Minister Sergey Lavrov accused Washington of wanting to keep Moscow and Kyiv "in a state of hostilities" for "as long as possible."

"Negotiations are difficult because the Ukrainian side seems to have expressed understanding of the things that should be agreed upon during the negotiations, constantly changing its position, refusing its own proposals," Lavrov said. "It is difficult to get rid of the impression that they are being held by the hand by their American colleagues."

He alleged "it is unprofitable" for the U.S. "that this process be completed quickly."

"They expect to continue pumping weapons to Ukraine. Provocative statements are being made," he added. "Apparently they want to keep us as long as possible in a state of hostilities."

Video has emerged showing the devastation in Ukraine's besieged city of Mariupol.

Drone footage recorded Wednesday and released by a Ukrainian right-wing paramilitary group that has been incorporated into Ukraine's National Guard shows entire neighborhoods destroyed in Mariupol. Mere shells are all that remain of buildings and smoke is still rising from some of the wreckage. The video has been verified by ABC News.

Ukrainian troops are continuing to battle persistent efforts by Russian forces to seize the strategic port city in southeastern Ukraine.

-ABC News' Fergal Gallagher

Belarus announced Wednesday its decision to expel several Ukrainian diplomats and close the Ukrainian Consulate General in Brest.

"The Ukrainian embassy will continue to work in Belarus in a 1+4 format, that is, an ambassador and four staff members," Belarusian Ministry of Foreign Affairs spokesperson Anatoly Glaz said in a statement, according to the state-run news agency BelTA.

Fierce fighting between Russian and Ukrainian forces continued in Mariupol on Wednesday morning, with the Ukrainian government warning that as many as 100,000 civilians -- or 22% of the besieged port city's original population -- remain trapped there.

One Mariupol resident, Natalia, who managed to escape with her elderly parents and four cats, told ABC News her home had no electricity or heat and that she would have to scavenge for food and other supplies under Russian bombardment. She recalled seeing bodies strewn in the streets because residents had no choice but to leave them there.

"We understood anytime we might be killed by the next bomb," Natalia said during an interview Tuesday.

Pro-Russia separatist forces from the self-declared Donetsk People's Republic in Ukraine's disputed Donbas region said Wednesday that 562 civilians, including 110 children, were evacuated from encircled Mariupol to the occupied town of Bezymenne in the past 24 hours. A total of 4,621 civilians were evacuated from Mariupol between March 5 and March 23, according to the separatist forces.

Ukrainian technicians have started repairing damaged power lines in an attempt to restore external electricity supplies to the site of the Russian-controlled Chernobyl nuclear power plant that were entirely cut earlier in the week, according to International Atomic Energy Agency Director General Rafael Mariano Grossi.

Ukraine’s regulatory authority said work began Thursday and technicians had succeeded in repairing one section, but off-site electrical power was still down, indicating there was still damage in other places.

Emergency diesel generators have been providing backup power to the site since Wednesday, and the regulator has reported that additional fuel had been delivered to the facility, the IAEA said.

The regulator lost communications with the site on Thursday and, as a result, it cannot provide information to the IAEA about the radiological monitoring at the facility, according to Grossi.

The regulator is still receiving information about the situation there through senior off-site management of the plant, Grossi said.

The plant's disconnection from the grid will not have a critical impact on essential safety functions at the site, however, staff is facing increasingly difficult conditions.

At least 211 technical personnel and guards have been living at the site for more than two weeks, and there is concern about the availability of food reserves, the regulator said.

The IAEA said eight of the country’s 15 reactors remained operating. Radiation levels at the locations were normal, the IAEA said.

-ABC News' Zoe Magee