PARIS — France's GDF Suez has signed a deal with Gazprom to take a 9 percent stake in the yet-to-be-built Nord Stream gas pipeline, the companies said in a joint statement Monday.

An industry source said Wednesday that an agreement would be signed in Paris this week during Russian President Dmitry Medvedev's three-day state visit to France.

The same source said GDF Suez would get 1.5 billion cubic meters of gas per year from 2015 from the pipeline, as part of the deal.

GDF Suez had been in talks for over a year to join the project built by Gazprom and German utility E.On, which will carry 55 billion cubic meters of gas annually from Russia to Germany via the Baltic Sea from 2012.

"GDF Suez will be in the project before construction starts on the pipeline in April," the industrial source said earlier on Monday, asking not to be named.

The deal was to be officially signed Monday evening at the Elysee Palace by GDF Suez chief executive Gerard Mestrallet and Gazprom chief Alexei Miller, in the presence of French President Nicolas Sarkozy and Medvedev.

Medvedev traveled to France on Monday and is also set to discuss Iran and the purchase of a helicopter carrier.

GDF Suez will buy its 9 percent stake from current shareholders — 4.5 percent from E.On and the remaining 4.5 percent stake from Wintershall.

The source said this deal will allow GDF Suez to increase its gas supplies by 10 percent. GDF Suez currently buys between 12 bcm and 13 bcm annually.