The failure of key rebel groups to attend UN and African Union (AU) sponsored talks on peace in Darfur has left the international community scrambling to make the best of an increasingly difficult situation.

After the first two days of talks, held in Sirte, Libya, a UN-AU mediation team abandoned scheduled public meetings in favour of shuttle diplomacy. Rather than continue the talks without the Justice & Equality Movement (JEM) and the Sudan Liberation Army (SLA), the team is sending envoys to their respective leaders, Khalil Ibrahim in Juba and Abdel Wahed Mohamed el-Nur, in Paris.

“It is disappointing that the two leaders did not attend,” says a Western diplomatic source in Khartoum. “They represent significant groups in Darfur and there will not be a lasting peace without them.”

Although the insurgent groups have called for more time for the rebel factions to reach a common position, most agree that continuing with peace efforts is still worthwhile. “They are still the best way forward,” says a spokesperson for the UK’s Foreign & Commonwealth Office.

It is far from certain whether the rebel groups will reach a united position even if they are given more time. “The contention that talks cannot get under way without all the rebel parties there and sharing a single line is a huge mistake,” says Colin Thomas-Jensen, policy adviser at Enough, a joint initiative of Washington-based International Crisis Group and US think-tank the Center for American Progress. “It is a fiction that this will ever happen.”

Securing the re-engagement of the two main rebel parties will be difficult. Pressure can be applied on the two leaders, but international leverage is limited by the fact the West has little influence over the rebels’ main backers, Chad and Eritrea.

However, the JEM and SLA factions do not represent the entire Darfur population. Rather than wait for the rebels to adopt a common position, the international community might be better served by allowing a broader range of groups to be represented at the negotiating table. Although this runs the risk of further inflaming El-Nur and Ibrahim, who see themselves as the key figures in the process, the people of Darfur would at least feel that they had a stake in any final agreement.

“Any solution has to have buy-in on the ground, otherwise it will not be able to be implemented,” says Thomas-Jensen. “The organisers need to allow representation of all rebel groups, not just those with guns.”

Although the rebel groups are the centre of attention, it is the Khartoum-based government that bears the burden of responsibility for the lack of progress in ending the Darfur conflict.

The regime is held responsible for sponsoring the Janjaweed militants and its raids, which have resulted in killing and looting. Further government raids in South Darfur in recent weeks have also resulted in dozens of deaths, including those of 10 peacekeepers. The UN depicts Khartoum’s April air attacks on villages in the north of the region as “indiscriminate and disproportionate”, and in late October voiced concern at reports of the forced relocation of internally displaced people in South Darfur. “We continue to be concerned about the humanitarian situation,” says a UN spokesperson in Khartoum.

The government is also accused of hampering efforts to bring a 26,000-strong UN-AU peacekeeping force to the region. The force is due to assume its full responsibilities on 31 December, and established headquarters in North Darfur on 31 October.

The West is walking a diplomatic tightrope. When UK Prime Minister Gordon Brown said in late October that sanctions against Khartoum would be considered if peace talks failed, the response from President Omar al-Bashir was defiant. “What we suffer here in Darfur is caused by these three powers: Britain, France and the US,” he said.

If the international community fails to increase pressure on Khartoum, there is a risk not only that the Darfur problems will continue, but that the delicate north-south accord secured by the 2005 Comprehensive Peace Agreement will fail.

“If the north-south agreement collapses and there is a resumption of hostilities in the south, you would have a conflict as bloody and brutal as before, and as you have in Darfur now,” says Thomas-Jensen. “You would have a government with nothing to lose and neighbours such as Uganda and Ethiopia are also likely to be drawn in.”

On the other hand, the potential gains from peace - both humanitarian and economic - are considerable. A combination of the north-south civil war and the Darfur conflict has meant that one of the greatest untapped oil reserves in the region continues to go largely unexplored.

The country is under US sanctions, and most European companies are deterred by allegations that Khartoum’s oil earnings are being used to fund the fighting in Darfur. If the peace talks are successful, the bloodshed will stop and the resulting international investment could be used to rebuild the war-shattered country.