Protests ahead of Trump's arrival in the Philippines

Riot police have used water cannons to prevent hundreds of protesters reaching the US embassy in Manila, just a few hours before the arrival of President Donald Trump in the Philippines for a regional summit and the last leg of his Asia tour.

Carrying placards declaring "dump Mr Trump" and "down with US imperialism", the protesters were blocked by police in riot gear with shields and batons, and then showered with jets of water from a fire engine.

"Mr Trump is the CEO of the imperialist government of the US, said 18-year-old student Alexis Danday after the protesters were scattered. "We know he is here to push for unfair treaties between the Philippines and the US."

Mr Trump was expected to arrive in the Philippines at around 8 pm (AEDT) for meetings with leaders of the Association of Southeast Asian Nations (ASEAN) and other East Asian nations, fresh off an Asia-Pacific summit and bilateral visit in Vietnam.

The Philippines will be Mr Trump's last stop on a marathon tour that has taken him to Japan, South Korea, China as well as Vietnam.

Mr Trump will meet Philippine President Rodrigo Duterte in Manila, where he will try to shore up relations strained by the mercurial Duterte's notorious anti-US sentiment.

In Vietnam earlier on Sunday, Mr Trump said he was prepared to mediate in the dispute over the South China Sea, where four Southeast Asian countries and Taiwan contest China's sweeping claims to the busy waterway.

But Philippines President Rodrigo Duterte, host of two days of summit meetings that will bring together Southeast Asian and East Asian nations, said the thorny issue was better left untouched. All the claimants will be at the summit, except for Taiwan.

"We have to be friends, the other hotheads would like us to confront China and the rest of the world on so many issues," Duterte said at a pre-summit business conference in Manila.

"The South China Sea is better left untouched, nobody can afford to go to war. It can ill-afford a violent confrontation."

The United States and its former colony, the Philippines, have been strategic allies since World War II.

Leaders of the 10-member Association of Southeast Asian Nations (ASEAN), China, Russia, Japan, Canada, South Korea, India, Australia and New Zealand arrived one by one for a glitzy gala dinner where they were entertained by singers and dancers.

Reuters / Newshub.