* Sudan offers million dollar discounts to sell seized crude
* North Asian trader loads cargo, heading to Singapore -trade
* At least seven tankers held up at Port Sudan (Adds comments, details on vessels)
By Luke Pachymuthu and Florence Tan
SINGAPORE, Jan 27 (Reuters) - Sudan has sold at least one cargo of crude seized from South Sudan at millions of dollars discount and is offering more, industry sources said, as Khartoum 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 from crude cargoes.
The seized crude was loaded onto three tankers from Jan. 13-20, South Sudan's justice ministry said.
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.
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 the United Arab Emirates port of Fujairah, they added.
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.
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 (CNPC), Malaysia's Petronas and India's Oil & Natural Gas Corp.
A third trader said buyers could declare force majeure if they still cannot lift the oil 30 days from the date of loading.
"Force majeure is the last resort if the cargo has not been loaded 30 days after the scheduled loading date. As long as the ship has not loaded the oil," the trader said.
"It will be complicated to declare force majeure if the oil is already on board. How are you going to discharge the oil back into the shore tanks?"
South Sudan became independent in July under a 2005 peace agreement with Khartoum that ended decades of civil war but both sides have failed to agree how to untangle their oil industries. SUDAN'S OIL SALES VESSEL TYPE STATUS DESTINATION Ratna Aframax 600,000 barrels Singapore/Jap Shradha Nile Blend loaded an
Jan. 19-20 Sea Sky Aframax 605,784 barrels off Sudan
Dar Blend loaded port
Jan. 13-14 Al Nouf Aframax 750,000 barrels Fujairah
Dar Blend loaded
TABLE OF OIL TANKERS AT PORT SUDAN VESSEL TYPE STATUS Esther Aframax To load Dar Blend Spirit Petrovsk Aframax To load Dar Blend Front Aframax To load Dar Blend Symphony Front Aframax To load Dar Blend Warrior Vermillion Aframax To load Dar Blend Energy Hellenspont Aframax To load Nile Blend Tatina Nordic Aframax To load Nile Blend Zenith Source: Reuters Freightview, trade (Additional reporting by Yaw Yan Chong and Osamu Tsukimori in TOKYO Editing by Manash Goswami and Simon Webb)