The Philippines' defence chief says he has told the US military that plans for joint patrols and naval exercises in the disputed South China Sea have been put on hold.

Key points: Duterte says 'this year would be the last' of joint US military exercises

Duterte says 'this year would be the last' of joint US military exercises The defence chief, who earlier signalled the importance of US ties, alerts Washington

The defence chief, who earlier signalled the importance of US ties, alerts Washington Analysts say the move undermines the US' ability to deter China in the South China Sea

This is the first concrete break in defence cooperation after months of increasingly strident comments by the country's new President Rodrigo Duterte.

Defence Secretary Delfin Lorenzana also said that 107 US troops involved in operating surveillance drones against Muslim militants would be asked to leave the southern part of the country once the Philippines acquires those intelligence-gathering capabilities in the near future.

Mr Duterte also wants to halt the 28 military exercises that are carried out with US forces each year, Mr Lorenzana said.

Mr Duterte has said he wants an ongoing US-Philippine amphibious beach landing exercise to be the last in his six-year presidency as he backs away from what he views as too much dependence on the US.

"This year would be the last," Mr Duterte said of military exercises involving the Americans in a speech on Friday.

"For as long as I am there, do not treat us like a doormat because you'll be sorry for it.

"I will not speak with you. I can always go to China."

Mr Duterte, who took office in June and describes himself as a leftist politician, has had an uneasy relationship with the US, his country's longtime treaty ally and former colonial master.

'Duterte's parochial democracy deeply troubling'

Mr Duterte has lashed out against US Government criticism of his deadly crackdown against illegal drugs, which has left more than 3,600 suspects dead in just three months, alarming Western governments and human rights groups.

But while some Filipino officials have walked back on Mr Duterte's sometimes crude anti-US pronouncements — early this week he told President Barack Obama "to go to hell" — Mr Lorenzana's comments show for the first time that the Duterte Government will act by rolling back cooperation with the US military.

Asked to comment on the possibility that the joint manoeuvrers will be the last under Mr Duterte, Major Roger Hollenbeck, the US military spokesman for the joint drills, replied: "If it's the last, so be it."

Mr Lorenzana said some US military officials have expressed concern about where the countries' 65-year-old treaty alliance is headed under Mr Duterte.

Mr Duterte's moves to limit the presence of visiting American troops will impede Washington's plans to expand the footprint of US forces in South-East Asia to counter China.

"President Duterte's shoot-from-the-hip style of parochial democracy is deeply troubling," Carl Thayer, an expert on the South China Sea, said.

"If Duterte moves to curtail US rotational military presence from bases in the Philippines, this would undermine the US ability to deter China not only in defence of Philippines sovereignty but regional security as well."

AP