Mr. Bashir, Sudan’s president, who is running for re-election in 2015, has publicly called for all blue helmets to leave Sudan. In November, he put that demand in writing, urging the United Nations to “prepare and implement an exit strategy.”

Some analysts said that Mr. Bashir may just be posturing and that his government benefits enormously from the money and veneer of peace that the mission generates. Still, a spokesman for the secretary general said in a statement on Thursday that the Sudanese authorities had asked two top United Nations officials to leave the country.

It seems unlikely that the Security Council will take new punitive measures against Sudan, with relations between Russia and the West at their lowest point since the Cold War. A case in point: The International Criminal Court wrote to the Council eight times in recent years, urging the world body to help secure Mr. Bashir’s arrest. The Council did not even write back. A former Council diplomat said that Russia and China said no response was necessary.

Years ago, when its relations with the West were less antagonistic, Russia did go along with an effort to refer Mr. Bashir to the international court. But things are different now, said Al Tayeb Zain El Abdin, a political scientist at the University of Khartoum. The Sudanese government used to ask Russia to use its veto on the Council, he said, “especially when referring Darfur to the I.C.C., but Russia refused.” Now, he said, “Russia is in a new mood.”

This month, Ms. Bensouda, the court’s chief prosecutor, said without concrete help from the world’s most powerful body, there was nothing more she could do to advance the case.

“If there was full political will of all the members on the Security Council, then something would have happened,” she said in an interview in New York.

She took pains to say that she had no intention of dropping the charges against Mr. Bashir. A warrant for his arrest remains in effect, she warned, and countries that belong to the court have a legal obligation to arrest the Sudanese president when he visits their territory.