U.S. President Barack Obama on Friday called Indonesian President Susilo Bambang Yudhoyono to express condolences for the loss of life and devastation caused by the earthquake in West Sumatra.

In the phone conversation, President Obama "received an update from President Yudhoyono on the situation on the ground and reiterated his offer, on behalf of the United States, to do everything we can to help alleviate the suffering and provide assistance to the relief operation," said the White House in a statement.

At least 1,100 people in Indonesia's South Sumatra were killed by two strong earthquakes in the past two days, top UN humanitarian affairs official John Holmes said Thursday, adding that the death toll could rise.

Indonesian officials said almost 3,000 people have still been trapped under rubble.