May 26 Niger's President Mamadou Tandja dissolved parliament on Tuesday after the constitutional court ruled his plan to hold a referendum on a law allowing him to stand for a third term in office was illegal.
Niger, a desert country of 15 million people in northwest Africa, is attracting increasing investor interest in its uranium deposits. It produces around 7.5 percent of the world's uranium, according to the World Nuclear Association.
Below are details of companies with uranium mining and exploration projects in Niger.
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, 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 URANIUM CORP
The Chinese state-owned firm known as SINO-U will invest $300 million in the Somina project, located at Azelik near Agadez. The project, due to come on stream by 2010, will produce around 700 tonnes per year.
Indonesian mining, energy, construction and infrastructure firm Earthstone Group owns four uranium blocks in Niger.
KOREA RESOURCES CORP
South Korean state-owned Korea Resources Corp signed a memorandum of understanding in March to buy around 10 percent of its annual uranium needs from Niger.
NIGER URANIUM (URU.L)
London-listed Niger Uranium owns eight prospecting licences in the Tim Mersoi Basin, which it describes as the world's fifth most important uranium producing district.
NGM RESOURCES NGM.AX
Australian-listed NGM Resources owns three uranium exploration concessions in Niger via its subsidiary Indo Energy.
(Sources: World Nuclear Association, company websites, Reuters data)
(Compiled by Daniel Magnowski; editing by Tim Pearce)