A delegation of rebels from the Central African Republic (CAR) have arrived in Gabon, where talks with the government they are trying to topple are set to get under way in the coming days.

Talks had been expected to start on Tuesday, but a plane carrying the government delegation along with members of the country's political opposition failed to leave Bangui, the capital, as scheduled.

Denis Sassou-Nguesso, president of the Republic of Congo, said negotiations were to begin no later than Friday.

He met the embattled leader of CAR, Francois Bozize, on Monday.

Sassou-Nguesso declined to comment on reports that rebels, who now control much of the country's north, are still seeking Bozize's ouster as a condition of the talks.

"In our capacity as mediator, we can't interpret the declarations of others," he said. "The fact that we hold to is that all the parties have agreed that we are going to negotiations."

Earlier on Monday, Eric Massi, who identifies himself as a spokesman of the rebel alliance, collectively known as Seleka, reiterated calls for the removal of the president, saying he has "lost all credibility" to lead the country.

"He has to leave power," Massi told Al Jazeera from Paris.

He rejected Bozize's offer to form a coalition government with the rebels, instead calling for a "peaceful transfer of power".

Commenting on the delayed flight carrying the government delegation, Abdoulaye Issene, president of the CPJP, a rebel group that signed a peace agreement with the government, said passengers were told it was cancelled due to a "technical problem" and would fly to Gabon early on Tuesday.

Necessary dialogue

The upcoming meetings between rebels, the government and the country's political opposition in Libreville, Gabon, come a month after fighters from several armed groups began their rebellion against a government that has wielded little power over its vast and sparsely populated north.

While the rebels have halted their advance toward Bangui, they now hold a dozen cities and towns. The rebellion poses the greatest threat to Bozize's presidency since he himself seized power in 2003.

Bozize already has offered up the possibility of a coalition government, a proposal the rebels have dismissed. A rebel spokesman has said the fighters want Bozize gone, a stipulation that could derail talks altogether.

The government's chief mediator, Willibiro Sako, said the objective of the talks is "to try to look into the problems of our country and find solutions for the peace, security and development of Central African Republic."

"We have to start to enter into dialogue even if at times there were some who did not agree with each other," he said on Monday.

In the nation of 4.4 million, many have little faith the government will be able to reach a lasting agreement with the rebels, especially because multiple peace accords already have been signed over the years with several different groups.

"Even if the rebel leaders reach an agreement with the Bangui government, their people on the ground will not get their piece of cake,'' Henry Yenzapa, a history professor at the University of Bangui, told The Associated Press.

Source: Al Jazeera and agencies