US President Barack Obama on Wednesday pledged full support for relief effort in Nepal, as the Himalayan country is still reeling from a powerful earthquake and heavy casualties.

In a phone conversation with Nepali Prime Minister Sushil Koirala, the president offered "deep condolences" over the loss of more than 5,000 lives and massive destruction inflicted, the White House said in a statement.

"The president pledged that the United States will do all that it can to help the people of Nepal in their time of need," the White House said.

The Obama administration had offered 10 million dollars in aid, plus a nearly 130-person disaster-assistance response team to conduct assessments, coordinate the humanitarian response and provide search-and-rescue capabilities along with 45 tons of cargo.

Some US military personnel, who were sent to Nepal for a previously scheduled training exercise, are joining the recovery effort, the White House said on Monday.

Historical heritage sites in Nepal's capital of Kathmandu and its surrounding areas are among buildings razed in the 7.9- magnitude quake that befell on Saturday.

Four Americans were killed in the region of Mount Qomolangma, the world's highest, in an avalanche triggered by the tremor.

The devastating quake also jolted and inflicted casualties in neighboring India, Bangladesh, Bhutan and the Tibet Autonomous Region of China.

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