Oil major Total SA (TOT), along with partners Wintershall AG and StatoilHydro ASA (STO), has agreed to cut its stake in some Libyan oil interests to give the national oil company a bigger share, according to a document posted on National Oil Co.'s Web site.

Total and its two partners have agreed to cut their share of the assets concerned to 27% from 50%, National Oil Co. said in a statement in Arabic, posted on its Web site.

The foreign partners' share of gas production from the assets concerned is to fall from 50% to 40% and then to 30%, National Oil Co. said, without providing precise details as to the timeframe.

The new deal is part of National Oil Co.'s policy to renegotiate terms and conditions with foreign partners to increase its share, the Libyan company said.

The information garnered from National Oil Co.'s site makes it tricky to define exactly which assets are concerned.

The Libyan national company explicitly mentions the C137 block and the Al-Jurf field. However, Al-Jurf is an oilfield situated within the C137 block, according to Total's reference document.

National Oil Co. also explicitly lists Total's partners in the document, indicating the new terms could relate to at least two blocks: C137 and C17.

Total has a 75% working interest of the "second-party share" of both of these blocks, but with a different partner for each. The second-party share is the portion that goes to the foreign partners rather than to National Oil Co.

Wintershall has the remaining 25% of Block C137 and StatoilHydro has the remaining 25% of Block C17.

StatoilHydro confirmed having renegotiated terms in Libya.

"StatoilHydro's stakes in the Mabruk and Murzuk fields have been renegotiated, both with a reduced share," a StatoilHydro spokeswoman said.

"We expected this, we were warned by the government on it," she added.

Mabruk is part of block C17. Murzuk is part of another block, indicating that the impact of the new terms could go beyond blocks C17 and C137.

A spokesman for Total declined to comment.

Wintershall couldn't be reached for comment.

Total's share of production from Libyan projects amounted to 74,000 barrels of oil equivalent a day. The company's overall average daily hydrocarbons production for 2008 was 2.35 million boe/day.

-By Adam Mitchell and Oliver Klaus, Dow Jones Newswires, +33 1 40171756; adam.mitchell@dowjones.com

(Elizabeth Adams in London and Jan Hromadko in Frankfurt contributed reporting.)