Leading finance houses from around the world have pledged $1bn (�630m) towards a major new gas initiative in Nigeria.

It is part of a $2bn project being undertaken by Nigeria LNG, which liquefies natural gas for export to Europe and the US.

Nigeria currently flares - or burns off - a lot of the gas that is associated with oil extraction.

The Nigerian Government has promised to reduce the amount of gas it flares in order to reduce global warming.

The loan from the banks is billed as the biggest project financing deal ever made in sub-Saharan Africa.

Track record

It is an important sign that financial institutions are prepared to take the risk of investing in Africa despite the political unrest.

"We've got a track record that the lending institutions were prepared to trust," Andrew Jamieson, Nigeria LNG's managing director, told the BBC's World Business Report.

"We have demonstrated that we can operate in the country and operate well," he said, but admitted that it had taken two years to raise the cash and that there had been some reluctance to be overcome.

The firm's previous plants have been entirely financed from shareholders rather than through banks.

Nigeria LNG is jointly owned by Shell, TotalFinaElf, Agip and state-controlled Nigerian National Petroleum Corporation.