WASHINGTON • United States President Barack Obama plans to visit Laos next year to attend a regional economic summit, making him the first American president to visit that country.

He will make history when he attends an Asean conference in the poor, but economically growing country, which was massively bombed by the US during the Vietnam War, Deputy National Security Adviser Ben Rhodes said on Wednesday.

Speaking at a Washington think-tank, Mr Rhodes said his own recent visit to Laos had helped lay the groundwork for Vientiane's Asean chairmanship next year.

Mr Obama will be travelling to Malaysia later this month to participate in this year's Asean summit. He has made a point of attending the event as his administration seeks both to boost the group's standing and underscore the seriousness of an announced US "pivot" towards Asia and the Pacific.

Touching on the past between Laos and the US, Mr Rhodes said Washington could do more to clear unexploded ordnance that has been lying menacingly in Laos' fields since the Vietnam War.

US warplanes dropped more than two million tonnes of ordnance on Laos from 1964 to 1973, in about 580,000 bombing missions aimed at cutting North Vietnam's supply lines through the neighbouring country.

An estimated 30 per cent of the ordnance failed to detonate.

Laos and the US have improved relations during Mr Obama's presidency. US ties with Vietnam and Myanmar have also been strengthened.

In 2012, Mrs Hillary Clinton, now a Democratic presidential hopeful, became the first US secretary of state to visit Laos in more than half a century.

AGENCE FRANCE-PRESSE