From the BBC:
President Omar al-Bashir told state TV: “The government of Sudan welcomes all financial, material, logistic or technical assistance from the UN in order to strengthen the AU mission in Darfur.” His Foreign Minister Lam Akol specified that “there should be no talk about a mixed force”. He told the BBC there would be no UN troops.
And the NY Times reveals that:
It was not clear what made the Sudanese leaders change their minds. But a United Nations official who was present said the Chinese ambassador to the United Nations, Wang Guangya, had played a role in persuading Sudan’s foreign minister, Lam Akol, that there was no hidden agenda in the effort to introduce a stronger peacekeeping force. The official spoke on condition of anonymity, citing diplomatic protocol.
See also an interesting IRIN report on Sociolingo’s blog.
— Update —
Could this have anything to do with the fact that Chad has recently switched allegiance from Taiwan to China? And that it might have started asking for some help from its new Asia ally in solving its problems with Sudan in the context of the Darfur conflict?