Sudan's ambassador to the United Nations criticized the United States Tuesday for supporting possible prosecution of the country's president, even as the government takes a step toward peace in Darfur.

Ambassador Abdalmahmood Abdalhaleem Mohamed said it was "ironic" that the United States, which refused to become a party to the International Criminal Cout, is now supporting its possible prosecution of Sudan' President Omar al-Bashir on genocide charges.

Mohamed spoke after Sudan's government and Darfur's most powerful rebel group agreed Tuesday to launch negotiations on ending the six-year war in Darfur.

The Sudanese government is hoping that by showing seriousness about peace, it can avert prosecution of al-Bashir by the Hague-based court on accusations he orchestrated atrocities against Darfur's ethnic Africans.

The war in Darfur began in 2003 when rebel groups took up arms against the government complaining of discrimination and neglect. So far up to 300,000 people have died and 2.7 million have fled their homes, according to U.N. officials.

U.S. Ambassador Susan Rice was very lukewarm about Tuesday's agreement between the government and the rebel Justice and Equality Movement, and she told reporters there was "no linkage" between the possible prosecution of al-Bashir and the talks to launch peace negotiations.

Tuesday's agreement to launch negotiations "is potentially a modest first step, but it is not itself a cessation of hostilities," Rice told reporters. "The United States' position has been and remains that we see no circumstances or other actions to date that would change our judgment at this point that (such a) deferral is unwarranted."

Rice also said Tuesday the United States "remains deeply concerned about the ongoing genocide in Sudan" and called for full deployment of a 26,000-strong U.N.-African Union peacekeeping force in Darfur which the U.S. views as "a critical element" for protecting civilians.

Mohamed argued that Rice failed to note what he called "the remarkable progress" in Tuesday's agreement.

The U.S. objective from the court "is regime change, and our country and our people are fully united behind our president. They will never achieve their goal," Mohamed said.

After President Barack Obama took power, he said, "we were expecting a change in the U.S. policy" toward Suday. "What we are seeing now shows us that nothing has changed," he said.

A spokesman for the U.S. Mission to the United Nations provided no additional comment on the Sudanese ambassador's statements.