French oil services group Technip is well placed in association with Japanese JGC Corporation to win a contract worth 3.8 billion euros to build a refinery in Vietnam, a source close to the matter told AFP on Wednesday.

"A consortium composed of Technip and JGC has been retained by the Vietnamese state oil group Petrovietnam," the source said.

But no agreement had yet been signed, the source said. Work on final details of the contract could take weeks or several months.

The project, costing the equivalent of 5.0 billion dollars, is for the construction of the biggest refinery in Vietnam with capacity exceeding 200,000 barrels per day.

Technip declined to comment to AFP beyond saying that it had already worked on a project in Vietnam.

A consortium formed of Technip, JGC and Spanish company Tecnicas Reunidas has built a refinery at Dung Quat in Vietnam which began operating in 2009. It has production capacity of 140,000 barrels per day.

The price of shares in Technip was showing a gain of 3.10 percent to 74.07 euros in early trading on Wednesday, marking the biggest rise among shares quoted on the CAC 40 index which was showing an overall fall.