French nuclear energy giant Areva signed a deal with Mongolia's state-owned Mon-Atom on Saturday to develop two uranium mines in the Gobi desert, officials said.

Areva said in a statement that the agreement would create a company that would be 66 percent owned by Areva and 34 owned by Mon-Atom, and that Japan's Mitsubishi Corporation would take an equity interest.

Further details of the deal, which was signed during a visit to Mongolia by French Foreign Minister Laurent Fabius, were not immediately announced.

Fabius' Mongolian counterpart, Luvsanvandan Bold, said the deal represented an important step for the resource-rich but still impoverished nation.

Areva, which has had a presence in Mongolia for more than 15 years, said that exploration work had discovered two uranium deposits with estimated reserves of 60,000 tonnes.

Mongolian protesters had warned before the signing that a deal could lead to the contamination of water resources in the area.

"We are not against cooperation with France... We support cooperation in between our countries in all areas. But we just say 'no uranium exploration in Mongolia', as not having it is the best way to prevent radioactive pollution and contamination," said Selenge Lkhagvajav, one of the protest leaders.

Wedged between Russia and China, Mongolia has recently been seeking to broaden the base of its political and economic allies, notably exploring relationships with France, Japan and Germany.

Other deals signed on Saturday included agreements on cooperation on farming, culture,sport and tourism.