It's going to be OK

US President Barack Obama yesterday sought to ease growing Asian worries about the raucous election campaign to succeed him which has been dominated by the incendiary rhetoric of mogul Donald Trump, now the Republican Party's nominee.

"I think other people sometimes look at our election system and say 'what a mess'," Obama told a townhall meeting with young leaders in Vietnam's Ho Chi Minh City, formerly Saigon.

"But usually we end up doing okay because the American people are good people ... Sometimes our politics doesn't express all the goodness of the people," he said, without referring specifically to any of the presidential candidates.

Obama made the comments just before ending a three-day trip to Vietnam, whose high point was an announcement that Washington's ban on sales of lethal weapons to the country - a vestige of the Vietnam War - would be completely lifted.

Obama repeatedly insisted that lifting the embargo was not a response to Beijing's assertiveness in the South China Sea. Critics accused Washington of throwing away a powerful lever it had to press communist-ruled Vietnam for improvements in human rights.

White House officials say the arms move was a natural step to take with a country that, once an enemy, is now a key part of Obama's strategic 'rebalance' towards Asia and an important trade partner as its economy grows apace.

Obama also announced the Peace Corps would begin operating in Vietnam for the first time.

Thousands of people lined the streets of Ho Chi Minh City for a second day to cheer enthusiastically and wave mini-flags of Vietnam and the United States as Obama drove by on his way to the airport for a flight to Japan.