FACTBOX-Foreign investment in Niger

July 3 (Reuters) - The United Nations, United States, France and the EU have this week criticised Niger's President Mamadou Tandja's plan to hold a referendum to enable him to extend his rule over the West African uranium producer beyond the expiry of his second term in office.

The plan, declared unlawful by the country's constitutional court, has met with internal opposition, while the international community says it threatens to undermine democracy and destabilise the country.

Below are details of companies with mining, oil and industrial projects in Niger, a desert country of 15 million people which produces around 7.5 percent of the world's uranium.

AREVA (CEPFi.PA)

French state-owned nuclear energy group Areva is developing the Imouraren uranium mine in the north of Niger. Due to begin producing in 2012 after initial investment of 1.2 billion euros, Imouraren is expected to be the biggest uranium mine in Africa with eventual production of 5,000 tonnes per year for 35 years.

Areva has operated Niger's two existing uranium mines, Cominak and Somair, since the 1970s.

CAMECO (CCO.TO)

Cameco, the world's biggest uranium producer, last year bought an 11 percent stake in Govi High Power Exploration, which owns exploration properties around Arlit and Agadez in Niger.

CHINA NATIONAL PETROLEUM CORP

Chinese state-owned CNPC struck a $5 billion deal with Niger's government last June to pump oil from the Agadem block within three years, and lay a 2,000 km pipeline to export it.

CNPC also said it would build a 20,000 barrels per day oil refinery, which would be Niger's first. President Tandja laid the foundation stone of the Ganaram refinery in October last year. The deal, which included a 127 billion CFA franc ($272.5 million) signature bonus, was criticised by rights groups for its intransparency.

CHINA NATIONAL URANIUM CORP