US President Barack Obama called Nepalese Prime Minister Sushil Koirala Wednesday to offer US condolences and promise aid to the earthquake-damaged nation, spokesman Josh Earnest says.

"The president pledged that the United States will do all it can to help the people of Nepal in this time of need," Earnest says.

A USAID disaster response team on Wednesday reached the hard-hit city of Bhaktapur to work with the Nepali army and members of the community to find people who might be trapped, US State Department spokeswoman Marie Harf says. The US military also sent a 20-member humanitarian assistance team to support the team.

In addition a USAID airlift of emergency shelter materials is headed to Nepal, she says. It consists of 700 rolls of plastic sheeting to help an estimated 30,000 to 35,000 people and is expected to land in Kathmandu early on Thursday.