SIRTE, Libya – Sudan’s government committed to a cease-fire in Darfur at the start of peace talks Saturday, but mediators and journalists outnumbered the few rebels who did not boycott the U.N.-sponsored negotiations, reducing hopes for an end to the fighting.

The large government delegation said its cessation of hostilities was a sign of goodwill for negotiations aimed at ending over four years of fighting in the western Sudanese region. But the pledge was not matched by the rebels, whose main leaders all refused to attend the talks.

“The government of Sudan is proclaiming as of now a unilateral cease-fire in Darfur,” said Sudanese chief envoy Nafie Ali Nafie. “We shall not be the first ones to fire arms.”

The U.S. special envoy for Sudan, Andrew Natsios, praised the government for its pledge, but cautioned that dozens of previous cease-fire declarations in Darfur have been broken by both government troops and rebel factions.

Some 20 rebels were present in the vast conference hall in the Libyan coastal town of Sirte. Ahmed Diraige, the head of an obscure faction known as the Sudan Federal Democratic Alliance, spoke on behalf of the rebels and stated the groups present were also willing to consider a cease-fire.

But with the absence of major rebels, hopes faded for a quick peace agreement. Mediators downplayed the conference’s goals, saying the focus would now be to “create conditions” for effective peace talks. Mediation spokesman Ahmed Fawzi warned it would be “a long process.”

The host of the talks, Libyan leader Moammar Gadhafi, questioned what could be achieved in Sirte, saying the absence of the main Darfur rebel chiefs, Abdulwahid Elnur and Khalil Ibrahim, proved international mediation efforts were failing.

“I had expected my sons Abdel Wahid and Dr. Khalil to be here,” Gadhafi said. “These are major movements, and without them we cannot achieve peace.”

Elnur, the founder of the Sudan Liberation Army rebels, said immediately after the talks were announced that he would boycott until the U.N. and African Union have deployed a joint force of 26,000 peacekeepers due in January.

Ibrahim, the leader of the rival Justice and Equality Movement, had initially agreed to the talks, but on Friday announced he was also boycotting because mediators were inviting smaller, less representative rebel factions. Mediators insist they invited all factions to make sure the talks were inclusive.

Diraige, the main rebel delegate present, later said he felt Darfurians could still count on Gadhafi, an influential player in the region.All participants warned that the absence of a broadly accepted peace agreement could greatly weaken the mission of the joint AU-UN force.

Although the government’s cease-fire announcement raised hopes that momentum for peace could still be generated, Sudan’s military has regularly bombed Darfur rebel zones and sent proxy-militias against villages despite previous pledges and U.N. resolutions.

Natsios warned that the U.S. could impose further sanctions against rebels or the government if they resume hostilities. “We are prepared … to hold all parties to their cease-fire agreement,” he told delegates at the talks.

Darfur’s ethnic African rebels took arms in 2003 against the Arab-dominated central Sudanese government, accusing it of decades of discrimination. Khartoum is accused of retaliating with mass violence against civilians that has killed more than 200,000 people and displaced over 2.5 million, largely ethnic Africans.

Also in attendance were several Arab ministers and senior envoys from the Arab League.

The opening of new negotiations in Libya was viewed as a sign that Sudan’s Arab neighbors want an increased role in peace efforts. It was also an attempt by Libya to show it has ended decades of international isolation and can play its part in regional diplomacy.

But many rebels have grown skeptical of the Arab states’ involvement, stating they are biased toward Khartoum.