US Deputy Secretary of State Robert Zoellick flew into the Nigerian capital today to increase pressure on the warring parties from Sudan's Darfur region to strike a peace deal before a midnight deadline.
The government of Sudan has accepted a draft settlement on security, power-sharing and wealth-sharing, but two Darfur rebel groups have so far refused to sign, insisting their key demands be met in full.
"One of the key points the [rebel] movements have to realise is they don't have a better option and it will be a disaster for them if they reject this deal. They will gain nothing and they will be discredited," said a diplomat who is closely involved.
"If Zoellick can help them realise that, it would be most helpful," he added.
The peace talks have dragged on for two years while the conflict in Darfur has escalated, and African Union (AU) mediators say failure to secure an agreement in Abuja will lead to yet more bloodshed and suffering in Darfur.
A collapse of the talks would also be a serious setback for the AU, which seeks African solutions to African problems.
The rebels took up arms in early 2003 in ethnically mixed Darfur, an arid region the size of France, over what they saw as neglect by the Arab-dominated central government.
Khartoum used militias, known locally as Janjaweed and drawn from Arab tribes, to crush the rebellion. The fighting has killed tens of thousands of people while a campaign of arson, looting and rape has driven more than two million from their homes into refugee camps in Darfur and neighbouring Chad.
Washington, which labels the violence in Darfur "genocide", is intensifying efforts to resolve the conflict. Secretary of State Condoleezza Rice called yesterday for a UN force to bolster a 7,000-strong AU peacekeeping mission in Darfur.
But Khartoum has so far rejected the idea of such a force.