South Sudan says it was forced to suspend its participation in the unity government with Sudanese leaders in Khartoum because no amount of negotiation could get President Omar al-Bashir to implement key parts of a 2005 peace deal. As Nick Wadhams reports from Nairobi, the move raises fears that a peace process once so full of hope has collapsed.

The South Sudanese ambassador tells VOA News that his leaders had run out of patience with the Khartoum government's actions, which he said included raids on offices of the Sudan People's Liberation Movement and harassment of its members.

John Andruga Duku says that the ball is now in Khartoum's court. South Sudan is ready to come back into the government and avoid conflict. But he says Mr. Bashir must reverse course, quit stalling and implement the Comprehensive Peace Agreement of 2005.

"It is they who are really in charge because we are not the one who are holding this process, it is they. If they want to push the button to go to war, it is they do it. But on our side, we have no intention to go to war. Ours really its to say that there are some difficulties and there is obstruction in implementation of CPA. We want to come forward and implement them so that we move forward," he said.

The 2005 Comprehensive Peace Agreement between north and south Sudan ended more than two decades of civil war between the largely Christian Sudan People's Liberation Army in the south and the forces of the Sudanese government in the north, which is mostly Muslim.

But the deal had shown signs of strain in recent months, especially after the United Nations concluded that the north was refusing to withdraw some of its troops from areas of the south it had agreed to vacate. Tensions rose to a peak last week, when the Sudan People's Liberation Movement suspended its cooperation with the unity government.

In the days since, Khartoum has repeatedly urged it to drop its opposition. Government officials say they are committed to the comprehensive peace agreement and the various requirements of the deal will just take time.

Mr. Duku says the international community also shares some of the blame for the crumbling of the peace deal. He says it is too focused on the Darfur conflict in Sudan's west, and has not delivered some of the billions of dollars promised in Oslo, Norway, after the peace deal was signed.

"We are disappointed because there is this focusing on Darfur and a lot of feeling from the international community that maybe in the South there is now agreement and let us focus on Darfur and that allow the sit to arrive where it is today. And we believe the international community must have an obligation because in Oslo when they pledge the so-called fopur-point-five-billion U.S. dollars for peace dividend, they did not live to that obligation," he said.

Earlier this year, the United States accused Sudan's government of delaying implementation. According to the peace deal, south Sudan gets six years of autonomy leading up to a referendum in 2011. Its people will then decide whether to secede from Sudan.