World Bulletin / News Desk

The Philippines and the United States launched war games on Tuesday against the backdrop of the unusual threat of American forces being ejected from the Southeast Asian nation, as its firebrand leader pivots to China.

Duterte has in recent days warned the war games will be the last of his six-year term, and threatened to scrap a defence pact implemented by his predecessor that was meant to see more US troops in the Philippines to counter Chinese expansion in the South China Sea.

"Better think twice now because I will be asking you to leave the Philippines altogether," Duterte said on Sunday in his latest outburst against the Americans, full of typical invective.

"The Americans, I don't like them... they are reprimanding me in public. So I say: 'Screw you, fuck you'," he said, while signalling again that he wanted to forge closer alliances with China and Russia. 

Last week Duterte, 71, also claimed the CIA was plotting to assassinate him.

This came after he branded Barack Obama a "son of a whore" in response to being told the US president planned to raise human rights concerns over his drug war.

Duterte has vowed to eradicate illegal drugs in the Philippines, warning the nation is in danger of becoming a narco-state.

His crime war has seen more than 3,000 people killed, with the United Nations, the European Union and rights groups raising concerns about alleged extrajudicial killings and a breakdown in the rule of law. 

Duterte has insisted he is not doing anything illegal, yet at the same time said he would be "happy to slaughter" three million drug users. 

He also likened his crime war to Nazi leader Adolf Hitler's effort to exterminate Jews, but following an outcry apologised for referring to the Holocaust.