The next few months will be crucial for Sudan as it prepares to hold two referenda on self-determination in January, top United Nations officials said today, urging all parties to redouble their efforts to ensure that the polls are held on time, free, fair and credible.

On 9 January the inhabitants of southern Sudan will vote on whether to secede from the rest of the country, while the residents of the central area of Abyei will vote on whether to be part of the north or the south.

The referenda will be the final phase in the implementation of the Comprehensive Peace Agreement (CPA), which was signed in 2005 to end two decades of conflict between the northern-based Government and the Sudan People's Liberation Movement/Army (SPLM/A) in the south.

"This peace process is unique in the history of the Sudan and the next few months will be critical for safeguarding the achievements made since the signing of the Comprehensive Peace Agreement," Secretary-General Ban Ki-moon writes in his latest report to the Security Council on Sudan.

"As the Comprehensive Peace Agreement deadline for the referendums approaches, public anticipation and anxiety are building up at an accelerated pace. The events of the next three months will have a profound impact on the future of the Sudan.

"The stakes are undeniably high, as failure to meet the deadline for the referendums prescribed by the Comprehensive Peace Agreement could have severe consequences. Notwithstanding the progress made so far, it is imperative that the parties to the Agreement and all relevant authorities redouble their efforts to ensure that they successfully meet the deadline," he states.

Mr. Ban notes that while international partners are eager and ready to support and assist the Sudanese people through this last phase of implementation of the CPA and beyond, it is, and must continue to be, a fundamentally Sudanese effort.

"International contributions have been important and will continue to be so long after the referendums, but only the political will of the Sudanese themselves can drive this process forward. As such, it is the parties to the Agreement that have the primary responsibility to ensure its success," he says, adding that there is no time left for political confrontation and stalemates.

The Secretary-General has set up a three-member UN panel to monitor the referenda, at the request of the Sudanese Government. In addition, the UN Mission in Sudan (UNMIS) is providing technical, logistical and other assistance for the preparations for the referenda.

Under-Secretary-General for Peacekeeping Operations Alain Le Roy told a meeting of the Council today that there has been "palpable" progress in the preparations for the southern Sudan referendum, but there was a lack of progress on the Abyei referendum, for which a referendum commission has still not been set up.

He stressed that it is essential that the parties reach agreement, noting that a lack of progress is exacerbating tensions on the ground.

Mr. Le Roy recalled that during the Council's recent mission to Sudan, Southern Sudan President Salva Kiir warned of the serious risk of violence during the referendum and urged the creation of a buffer zone between north and south.

"We are currently considering a number of possible options to increase UNMIS' presence in high-risk zones along the border, especially traditional migration zones or those where population movements could take place," he said.

"However," he added, "it remains important to recognize that an increase in the number of troops would not enable UNMIS to prevent or to contain a clash between the two armies. Our best possible tool against a return to war remains our commitment in favour of a political agreement, i.e. the agreement of the parties on key pending issues."

Mr. Le Roy added that, as the attention of the international community increasingly turns to the impending referenda, it is important not to lose focus of the acute challenges remaining in Darfur.

During the reporting period, he said, incidents of banditry, carjacking, ambushes and abductions of UN staff and humanitarian workers continued in the strife-torn region.

In his recent report to the Council on the joint UN-African Union peacekeeping mission in Darfur (UNAMID), Mr. Ban noted that clashes between Government and rebel forces have destabilized some areas of the region, caused new displacements and impeded the delivery of humanitarian aid.

"I call upon all belligerents to cease hostilities and join the peace process for the sake of the people they claim to represent," the Secretary-General said.