Singapore: Sudan has sold at least one tankerload of crude seized from South Sudan, according to industry sources who said Khartoum appears to have attracted buyers with a steeply discounted price as it looks to recover oil revenue from its former civil war foe.

A bitter row has escalated between the two over the value of the transit fee landlocked South Sudan should pay for oil pumped north by pipeline through its northern neighbour and exported from Port Sudan.

South Sudan is shutting down production in protest after Khartoum blocked exports and seized some of the oil as compensation. South Sudan's President Salva Kiir accused Khartoum of having "looted" revenues amounting to roughly $815 million (Dh2.9 billion) from crude cargoes.

The seized crude was loaded onto three tankers from January 13-20, South Sudan's justice ministry said.

Final price unclear

Sudan sold one of those cargoes, a 600,000 barrel shipment loaded on the vessel Ratna Shradha, to a North Asian trader. The final price of the sale was unclear, but one trader said that the cargo was sold at a discount as steep as $14 a barrel.

That would indicate an $8.4 million discount for the whole cargo versus the last official price charged by the South.

"This is crude from the South sold by the North at a $14 discount to the South's last selling price," a Middle East-based crude trader said.

The tanker is heading to Singapore, another source said, and this was confirmed by AIS Live ship tracking data on Reuters.

The last time South Sudan sold Nile Blend cargoes, it did so at a premium of $2.50-$3.00 a barrel to the benchmark Indonesian Crude Price, traders said. This would indicate that Sudan has sold the cargo at a discount of around $11 a barrel to the Indonesian price.

Sudan has also loaded two other cargoes of seized Dar Blend crude, but it is not immediately clear if they have sold those.

Khartoum had offered these cargoes last week at a discount to official South Sudan prices, traders said. One of them is headed to Fujairah, they added.

A source familiar with Sudan's oil marketing strategy said that Sudan had around 10 million barrels available to sell from storage and pipelines.

"There's 10 million barrels in or on its way to Port Sudan. The North says it's their equity," he said.

The South last sold seven cargoes of Dar Blend at discounts between $5 and $11 a barrel to dated Brent. Sudan offered the cargoes at a discount of $15-$16, another source said.

The lure of deeply discounted oil is probably outweighing the risks buyers face of any legal complications for purchasing the cargoes from Sudan.

Buyers could face private arbitration or even be dragged to the International Court of Justice, said a lawyer familiar with contract arbitration, declining to be identified because he is not authorised to talk to the media.

Caught offguard

Regular buyers of South Sudan oil were caught offguard when Khartoum started blocking exports in late December.

In addition to the three, at least seven tankers are still waiting at the port to lift December and January cargoes, raking up demurrage costs of $20,000-$22,000 per day, traders and shipbrokers said. Buyers include PetroChina, Glencore, Vitol, Trafigura and Arcadia, they said.

"There was no reason given. They just held back sailing," a second trader with a Western firm said, adding that demurrage costs and the uncertainty were a "nightmare".

South Sudan pledged to fully shut its output of 275,000 barrels per day (bpd) in two weeks, a move that could also cut off supplies to equity holders China National Petroleum Corp, Malaysia's Petronas and India's Oil and Natural Gas Corp.