JUBA, Sudan (AP) — Sudan’s president will speak at independence celebrations in the south this weekend, officials said Monday, just days after he vowed to continue a military offensive in a border region.

Sudanese President Omar al-Bashir supported the January referendum that paved the way for the oil-rich south to secede and become the world’s newest country on Saturday. However, recent tensions in the border state of South Kordofan and the disputed region of Abyei have raised fears that the split could be a violent one.

The southern government said Monday that 30 African heads of state including al-Bashir will travel to Juba for this weekend’s celebrations. British Foreign Secretary William Hague and U.N. Secretary-General Ban Ki-moon also are expected to attend. Many issues remains unresolved around the split including oil rights and wealth sharing. Representatives from both sides spent have spent weeks negotiating in Ethiopia’s capital.

Two decades of civil war with northern Sudan decimated the oil-rich south and left more than 2 million dead on both sides. The south lacks infrastructure and basic services, is aid-dependent and suffers from frequent floods during its five-month-long rainy season.

Despite its rich oil reserves, the south has no refineries and must transport its oil through pipelines to a northern port on the Red Sea. Al-Bashir said in a June 22 speech that he would block the south’s access to the pipelines unless a favorable wealth-sharing agreement was reached.

U.N. peacekeepers are in the northern border state of South Kordofan, but a spokesman for the Sudanese government said Sunday they should leave immediately after the south becomes independent. Such a move could leave tens of thousands of southern-supporting civilians without U.N. protection. A U.N. spokeswoman in Southern Sudan said any such decision would be made by the U.N. Security Council.

Tensions in the area have displaced more than 70,000 people. Western advocacy groups have warned that al-Bashir’s government is attempting ethnic cleansing and even genocide in the region against the Nuba people, a black African group targeted in the 1990s in government-sponsored violence that left as many 200,000 Nubans dead.

Copyright 2011 The Associated Press.