U.S. Deputy Secretary of State Robert Zoellick is traveling to Nigeria to try to help the parties in the Darfur conflict reach a peace agreement. U.S. officials say only a few issues remain outstanding in the talks in the Nigerian capital, Abuja.

The deputy secretary of state has made several trips to Sudan and elsewhere in the region since becoming the Bush administration's policy "point man" for Darfur more than a year ago.

State Department Spokesman Sean McCormack says Zoellick has decided to go to Abuja, because only a few issues remain unresolved in the talks, and he believes his personal intervention could help produce the long-sought peace accord. "Although we are now down to a few issues in this regard, nothing is done, until everything is done. And Deputy Secretary Zoellick is going there in hopes to move the process forward on the ground, bring the parties together, and help them resolve any remaining differences," he said.

McCormack said that, in any negotiation, you have to pick your spots, and that the deputy secretary decided that this is the right moment to engage personally to try as he put it, to "get this over the goal line."

The Sudanese government has said it is willing to sign a draft peace accord from the African Union. But Darfur rebels have sought changes in the power-sharing accord, including stronger representation in Sudan's central government and better terms for integrating their forces into the Sudanese army.

In a written statement announcing the Zoellick mission, the State Department urged the Khartoum government to send a senior representative back to Abuja to finalize the peace agreement.

It said all parties should make a concerted effort to seize the opportunity for peace.

The Abuja talks have dragged on for two years, without a breakthrough in efforts to end the violence in the western Sudanese region. African Union mediators had set a Sunday deadline for reaching a final accord, but have extended it another 48 hours.

Officials here say Zoellick expects to meet in Abuja with Nigerian President Olusegun Obasanjo and other African Union leaders, and with commanders of the A.U. observer mission in Darfur, which the United States hopes to upgrade to a full-scale U.N. peacekeeping mission.

The Sudanese government has resisted the upgrade in the absence of a peace accord in Abuja. U.S. officials say the conversion of the A.U. mission to a so-called "blue-hatted" U.N. force -- doubling its size -- should go forward in any case.

Spokesman McCormack gave no return date for Zoellick, but said the deputy secretary's mission was not open-ended.