South Sudan seceded from Sudan on July 9, taking with it about 75 percent of the former united country's roughly 500,000 barrels per day of oil output. To export crude, South Sudan must send it north through a pipeline in Sudan to a Red Sea port.

Officials decided to stop the government of South Sudan's oil exports — roughly 200,000 barrels per day — on Nov. 17, Ali Ahmed Osman told reporters, adding the pipeline was still running and international companies would not be affected.

"We stopped exportation of the southern oil. We gave them four months free, without any sort of agreement," he said, adding Sudan would not resume the exports until the two sides agreed how much South Sudan would pay as a transit fee.

South Sudan has been selling about 200,000 barrels per day of oil since it declared independence, according to figures provided by the country's Petroleum Ministry last week.

Sudan had been allowing South Sudan to continue exporting without a final agreement on the expectation that the fees would be paid after a deal. Osman said South Sudan owed Sudan some $727 million in arrears between July 9 and the end of October.

International companies would be allowed to continue exporting their shares of oil normally, he added.

"We're not going to shut the pipeline, we're not going to shut any well, we're not going to stop any company, because we have an agreement with the companies. The share of the companies will be exported."

But a South Sudan oil official said a 600,000 barrel oil shipment sold by South Sudan to China's Unipec did not load as scheduled on Monday because of Sudan's decision to halt South Sudan's oil exports.