Russia said Monday it will extend the Black Sea Grain Initiative after it expires on March 18, but only for 60 days. The announcement came after consultations between U.N. representatives in Geneva and Russian Deputy Foreign Minister Sergei Vershinin.

"The Russian side, noting the package nature of the Istanbul agreements proposed by UN Secretary General António Guterres, does not object to another extension of the Black Sea initiative after the expiration of the second term on March 18, but only for 60 days," Vershinin said, according to Russian media reports.

Russia's consultations in Geneva on the grain deal were not easy, Vershinin said. Russia will rely on the effectiveness of the implementation of the agreement on the export of its agricultural products when deciding on a new extension of the grain deal, according to reports.

Ukraine, which is a key world exporter of wheat, barley, sunflower oil and fertilizer, had its shipments blocked in the months following the invasion by Russia, causing a worldwide spike in food prices. The first deal was brokered last July.

Russian forces suffered more than 1,100 dead in less than a week during battles near the eastern Ukrainian city of Bakhmut, the focal point of fighting in eastern Ukraine, President Volodymyr Zelenskyy said on Sunday.

During his nightly address, Zelenskyy described the battles as "Russia's irreversible loss."

Russian forces also sustained about 1,500 "sanitary losses," meaning soldiers were wounded badly enough to keep them out of further action, Zelenskyy said.

Dozens of pieces of enemy equipment were destroyed, as were more than 10 Russian ammunition depots, Zelenskyy said.

-ABC News' Edward Seekers

The investigation into who was behind the Nord Stream natural gas pipeline explosion should be "objective, impartial and transparent," Russian Foreign Minister Sergei Lavrov told Russian news agency Interfax.

"I do not want to threaten anyone. I do not want to hint at anything either. I just know that this flagrant terror attack will not go uninvestigated," Lavrov added.

Russia also said it will distribute its correspondence with Germany, Denmark and Sweden on the investigation of the Nord Stream explosion among the members of the United Nations Security Council soon.

Russia claimed the three countries are denying Russia access to information and participation in the investigation, first deputy permanent representative to the U.N. Dmitry Polyansky said in an interview, according to Russian news agency TASS.

-ABC News' Anastasia Bagaeva and Tanya Stukalova

Ukrainian President Volodymyr Zelenskyy denied that Ukraine had anything to do with the Nord Stream gas pipeline explosions last year.

"As for the Nord Stream, we have nothing to do with it," Zelenskyy said Friday.

The New York Times published a report that U.S. intelligence suggests that a pro-Ukrainian group sabotaged the pipeline.

Zelenskyy also suggested that the information being spread about the involvement of pro-Ukrainian groups in the attack could be done to slow down aid to his country.

-ABC News' Natalia Shumskaia

The leader of of Russia's Wagner mercenary group appeared on Sunday to ditch plans to withdraw his forces from Bakhmut in eastern Ukraine after receiving promises overnight that they would get all the arms needed to capture the devastated city.

Yevgeny Prigozhin said in a new audio message that the Kremlin has promised to resupply his Wagner Private Military Company with as much ammunition and weapons as they need.

Prigozhin said that for the first time he received a response to the situation regarding the shortage of ammunition. He said on Saturday night that the relevant companies promised to deliver everything necessary to continue the offensive in Bakhmut.

"Overnight we received a combat order, for the first time in all this time," Prigozhin said. "We have been promised as much ammunition and weapons as we need to continue further operations. We have been promised that everything needed to prevent the enemy from cutting us off (from supplies) will be deployed on the flank," he added.

In addition, Russian Army Gen. Sergei Surovikin will personally deal with issues of interaction between the Wagner PMC and the Ministry of Defense, Prigozhin said. "This is the only man with the star of an army general who knows how to fight," Prigozhin said of the Russian Defense Ministry assigning Surovikin to work alongside Wagner.

Surovikin commanded Russia's Ukraine campaign for several months before the chief of the General Staff, Army Gen. Valery Gerasimov, was given overall operational command above him.