Neither the United Nations nor the African Union can impose its will on Sudan, President Omar al-Bashir said on Thursday, amid mounting international pressure over its border conflict with South Sudan.

"We will implement what we want and, what we do not want, no one can impose upon us -- neither the UN Security Council nor the African Union Peace and Security Council," Bashir said.

He was referring to a May 2 UN Security Council resolution calling for Sudan and South Sudan to cease hostilities along their border and settle unresolved issues after the South's separation last July following a 1983-2005 civil war.

The remarks were Bashir's first about the resolution, and came a day after Sudan's army said it had fought with South Sudan along the disputed border on Wednesday, while the South said it came under renewed Sudanese air attack, violating a four-day-old UN-imposed ceasefire.

The UN resolution also ordered Sudan and South Sudan to pull troops back from their disputed frontier, effective Wednesday May 9, but Khartoum said it could not comply until there was a border agreement.

Bashir made his comments in an address to about 1,000 oil industry workers marking the "liberation" last month of Sudan's main oil region of Heglig, which South Sudan occupied for 10 days in a move coinciding with waves of Sudanese air raids against the South.