The last time Russia was the president of the Council was in February 2022, during the run-up to its full-scale invasion of Ukraine, a fellow UN member country.

Russia on Saturday assumed the presidency of the United Nations Security Council, the powerful body responsible for maintaining global peace and security, despite Ukraine urging member nations to block the move.

Presidency of the Security Council rotates alphabetically among its 15 members, with each country taking up the presidency for a month. The body is controlled by its five permanent members that includes the United States, United Kingdom, France, China, and Russia itself.

Saturday's move means the Security Council is being led by a country whose president was last month issued an international arrest warrant by the International Criminal Court, which is not a UN institution, for alleged war crimes.

Ukraine's Foreign Minister Dmytro Kuleba described Russia assuming the council presidency on April 1 as "the world's worst April Fool's joke," as Moscow's brutal invasion of Ukraine stretches into a second year.

"The country which systematically violates all fundamental rules of international security is presiding over a body whose only mission is to safeguard and protect international security," Kuleba said, noting it was a "stark reminder that something is wrong with the way international security architecture is functioning".

Ukraine's presidential adviser Mykhaylo Podolyak said the move was "another rape of international law... an entity that wages an aggressive war, violates the norms of humanitarian and criminal law, destroys the UN Charter, neglects nuclear safety, can't head the world's key security body".

Despite Ukraine's complaints and criticisms, the US said it could not block Russia - a permanent Council member - from assuming the presidency, a role that is mostly procedural.

Russian ambassador to the UN Vasily Nebenzia has told Russian news agency TASS that he planned to oversee several debates, including one on arms control, adding he would discuss a "new world order" that was coming to "replace the unipolar one".

Last year, Urainian President Volodymyr Zelensky called for the Council to reform or "dissolve altogether", accusing it of failing to take enough action to prevent Russia's invasion. He has also called for Russia to be stripped of its member status.

But the US has said its hands were tied as the UN charter does not allow for the removal of a permanent member.

"Unfortunately, Russia is a permanent member of the Security Council and no feasible international legal pathway exists to change that reality," White House press secretary Karine Jean-Pierre said this week, adding that the US expects Moscow "to continue to use its seat on the council to spread disinformation" and justify its actions in Ukraine.

A Security Council president is supposed to be neutral. But in its new role, Russia can maneuver meetings on Ukraine and use the month to portray the US and other Western countries as making false accusations against Moscow.