Sudanese President Omar el Bashir (r) holds hands with former leader of the Sudan People's Liberation Army John Garang

Two senior U.S. envoys have been sent to Sudan with the hope of keeping peace efforts there on track following the death of Sudanese senior vice president and former southern rebel leader John Garang. The Bush administration urged all Sudanese parties to keep working to implement the country's north-south peace accord.

In a move reflecting deep U.S. concern about the situation in Sudan following Mr. Garang's death, the Bush administration has dispatched two senior officials there for urgent talks with the parties to the country's north-south peace accord concluded earlier this year.

Assistant Secretary of State for African Affairs Constance Newman and the State Department's new special envoy for Sudan, Roger Winter, left Washington for Sudan only hours after the death of Mr. Garang in a helicopter crash was confirmed.

The U.S.-educated Mr. Garang, leader of the southern rebel Sudan People's Liberation Movement, or SPLM, became senior vice president of Sudan's new national unity government July 9 under terms of the peace accord ending the 22-year civil conflict.

He was a critical figure in the long-running negotiations for the comprehensive peace accord and a frequent visitor to Washington, and his death prompted an expression of deep sadness from the White House, which called him a visionary leader and true peacemaker.

White House Spokesman Scott McClellan said Mr. Garang was committed to moving forward on the peace process, and that a way for Sudanese to honor him would be to continue to move forward on implementing the agreement.

Secretary of State Condoleezza Rice, who last met Mr. Garang on a visit to Sudan two weeks ago, telephoned his widow, Rebecca, to express condolences and said in a written statement the United States remains firmly committed to the cause of peace in all of Sudan including Darfur.

Acting State Department Spokesman Thomas Casey said Assistant Secretary Newman and Mr. Winter will hold talks in Khartoum and in southern Sudan to help maintain the momentum of the north-south accord, which he said does provide for a process of succession for the unity government.

"I do want to point out that the peace agreement stipulates that a successor to Dr. Garang should be named by the Sudan People's Liberation Movement within two weeks," he said. "And we understand that its leadership is currently gathering in southern Sudan, and they'll be consulting on this issue. But we certainly are looking for, and hope to see, an orderly and peaceful succession to the new first vice president."

A senior official who spoke to reporters here said despite the reports of violence in Khartoum following Mr. Garang's death, U.S. officials are heartened by initial statements by his SPLM colleagues that they are committed to moving forward with the peace accord.

The official also said the United States has seen nothing to contradict official Sudanese accounts that the helicopter crash that took the lives of Mr. Garang and others aboard the aircraft was accidental, caused by bad weather.

He said the Sudanese government has begun an investigation of the crash that will include participation by the SPLM. He said there has thus far been no request for American technical assistance in the inquiry, but that the United States would be prepared to provide it if asked.