Russia on Monday vetoed a United Nations Security Council draft resolution that called on Sudan's warring parties to cease hostilities immediately and ensure the delivery of humanitarian aid.
All other countries of the 15-member council, including China, voted in favor of the measure drafted by Britain and Sierra Leone.
Russia was the sole member to vote against, in a move that British Foreign Secretary David Lammy said was "mean, nasty and cynical" and sent a message to the warring parties that they can act with impunity.
War erupted in April 2023 from a power struggle between the Sudanese army and the paramilitary Rapid Support Forces (RSF) ahead of a planned transition to civilian rule, and triggered the world's largest displacement crisis.
The draft resolution called on the parties to the conflict to "immediately cease hostilities and engage, in good faith, in dialogue to agree steps to de-escalate the conflict with the aim of urgently agreeing a national ceasefire."
It also called on them to engage in dialogue to agree humanitarian pauses and arrangements, ensure the safe passage of civilians and the delivery of adequate humanitarian aid, among other measures.
Russia accused the United Kingdom of attempting to meddle in Sudanese affairs.
"We agree with all Security Council colleagues that the conflict in Sudan requires a swift resolution. It is also clear that the only way to achieve this is for the warring parties to agree to a ceasefire," Deputy Russian UN Ambassador Dmitry Polyanskiy told the meeting.
He accused backers of the draft resolution of "double standards" when they were giving carte blanche to Israel to continue violations of international humanitarian law in Gaza, and said Lammy's criticism was an "excellent demonstration of British neo-colonialism."
"One country stood in the way of the council speaking with one voice. One country is the blocker. One country is the enemy of peace. This Russian veto is a disgrace, and it shows to the world yet again, Russia's true colors," Lammy told the meeting.
"I ask the Russian representative, in all conscience - sitting there on his phone - how many more Sudanese have to be killed? How many more women have to be raped? How many more children have to go without food before Russia will act?"
The UN says nearly 25 million people - half of Sudan's population - need aid as famine has taken hold in displacement camps and 11 million people have fled their homes. More than 3 million of those people have left for other countries.
