NAIROBI, Kenya - Kenya's political rivals have agreed to an independent review of the disputed presidential election, according to a copy of the deal obtained Friday by The Associated Press.

The agreement marks the first time government officials have agreed to a review of the Dec. 27 election results and was seen as a clear sign of progress in a dispute that has left 1,000 people dead in countrywide violence.

But power sharing remained a thorny issue. The preliminary agreement calls for the two sides to draw up a new constitution within a year, which could pave the way for a prime minister's post or another way to share power.

"We have only one outstanding issue ... the governance structure, which is being actively discussed. Several options have emerged,'' said a copy of the agreement obtained by The Associated Press.

The document indicated that negotiators would now consult President Mwai Kibaki and opposition leader Raila Odinga.

The deal was signed Thursday and witnessed by former UN secretary general Kofi Annan, who is mediating the dispute.

Kibaki was declared the winner of the election, but opposition groups claimed the results were rigged.

The ensuing violence has been shockingly brutal in a country once considered among the most stable in Africa, and ethnic resentments that flared with the bloodshed have polarized Kenyans as never before.

Much of the violence has been aimed at Kibaki's Kikuyu tribe, long resented for dominating politics and the economy.

The agreement called for an independent committee "to investigate all aspects of the 2007 presidential election.''

The committee is to include Kenyan and non-Kenyan experts, and it will start work March 15. Its report will be submitted within three to six months and then will be published two weeks later.

In the agreement, the government also acknowledged that the dispute cannot be resolved in court because the deadline for complaints expired earlier this year.

Kibaki's government had previously insisted the opposition take its complaints to the courts, while Odinga argued that Kibaki had stolen the vote and should step down.

The 10-point agreement also provides for a comprehensive reform of electoral laws and institutions, and the creation of a truth, justice and reconciliation commission.

The report also said politicians must examine how long-standing land grievances, accusations of ethnic favouritism, and frustration over poverty and corruption contributed to the violence.

On Thursday, U.S. President George W. Bush said he was sending Secretary of State Condoleezza Rice to Kenya. She was expected to arrive on Monday for meetings with Kibaki and Odinga and with civic leaders.

Bush said Rice will deliver a message to Kenya's leaders and people: "There must be an immediate halt to violence, there must be justice for the victims of abuse and there must be a full return to democracy.''

He made the announcement during a speech previewing his six-day trip to Africa, which starts Saturday. Bush's schedule does not include a stop in Kenya.