The Sudanese government has blocked oil exports from newly independent South Sudan, citing a transit fee dispute.
Landlocked South Sudan relies on its northern neighbor's pipelines and port on the Red Sea to export oil.
Sudan's oil minister, Ali Ahmed Osman, said Monday that Khartoum decided November 17 to hold up the south's oil shipments. He said South Sudan owes $727 million in unpaid fees through October.
South Sudan has accused Sudan of waging economic war by charging high transit and custom fees.
South Sudan took control of about 75 percent of Sudanese oil when it became independent July 9.
The two countries still are negotiating terms for sharing oil revenues. They also have not resolved which side will control the oil-rich Abyei region on the border.
Osman said Sudan's oil pipelines remain open.
Some information for this report was provided by AFP and Reuters.