Washington  - US President Barack Obama has appointed a former general to serve as his special envoy for Sudan's Darfur region, pledging to keep up the pressure on Khartoum to end the conflict.

Retired major general J Scott Gration has agreed to accept the post as international focus on Darfur intensifies following Sudanese President Omar al-Bashir's expulsion of humanitarian organizations from the country.

San Salvador, El Salvador  - US President Barack Obama on Wednesday called El Salvador's president-elect Mauricio Funes to congratulate him on his win.

Funes, a leftist who got 51 per cent of the vote in Sunday's election, put an end to a 20-year rule by right-wing party ARENA.

"The call was to congratulate me on the triumph obtained on March 15, to wish me success in my public management effort over the coming five years," Funes said.

Washington - Astronauts were steering a new solar panel into place using robotic arms on Wednesday ahead of a spacewalk to install the segment aboard the International Space Station (ISS).

The panel is part of a truss segment that will complete the backbone of the station and boost its energy capacity, allowing the crew size to double to six astronauts.

Los Angeles  - Two of the octuplets born in January to single mother Nadya Suleman were enjoying their first day at home Wednesday, hours after a raucous reception from paparazzi might have made the hospital seem calm.

The photographers and other onlookers clung to Suleman's vehicle as it drove up to the suburban Los Angeles home through a throng of hundreds awaiting the arrival of the celebrity babies and their controversial mother.

Washington - The US Federal Reserve, in a drastic new effort to keep the financial sector afloat, said Wednesday it would buy up more than 1 trillion dollars in Treasury and mortgage-backed securities.

Surprising many analysts, the US central bank said it would buy up to 300 billion dollars in long-term Treasury securities over the next six months and another 750 billion dollars in mortgage-related assets at the heart of the financial crisis.

New York  - The United Nations on Wednesday called on governments to sign and ratify the Convention on Cluster Munitions, which will ban the use, production, transfer and stockpiling of cluster bombs.

Since its adoption in Dublin in May 2008, the convention has been signed by 95 countries and ratified by four - the Holy See, Ireland, Sierra Leone and Norway.