The Philippine defense chief has told the US military that plans for joint patrols and naval exercises in the disputed South China Sea have been put on hold, the first concrete break in defense cooperation after months of increasingly strident comments by the country’s new president.

Delfin Lorenzana, the defense secretary, 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.

President Rodrigo Duterte also wants to halt the 28 military exercises that are carried out with US forces each year, Lorenzana said. 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,” Duterte said of military exercises involving the Americans in a speech on Friday in southern Davao city where he lashed out at the US anew.

“For as long as I am there, do not treat us like a doormat because you’ll be sorry for it,” Duterte said. “I will not speak with you. I can always go to China.”

In Washington, the state department spokesman, John Kirby, said the US government is not aware of any official notification on curtailing military exercises. He said the US remains focused on its security commitments to the Philippines, with which it has a mutual defense treaty.

“We think comments like this, whether they are or will be backed up by actual action or not, are really at odds with the closeness of the relationships that we have with the people of the Philippines and which we fully intend to continue,” Kirby told reporters.

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

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 Duterte’s sometimes crude anti-US pronouncements – early this week he told President Barack Obama “to go to hell” – Lorenzana’s comments show for the first time that the Duterte administration will act by rolling back cooperation with the US military.

With the turquoise backdrop of the South China Sea, US marines and allied Filipino combat forces barged ashore on Friday on amphibious vessels in a mock assault on a Philippine beach in San Antonio town in north-western Zambales province.

Pounding rain prevented military aircraft from joining the beach assault drills, but the US and Filipino forces managed to rapidly come ashore to take out a “notional target”, said Maj Roger Hollenbeck, a US military spokesman for the drills.

Asked to comment on the possibility that the joint maneuvers will be the last under Duterte, Hollenbeck replied, “If it’s the last, so be it.

“I have nothing to do with that and we are going to continue to work together, we’ve got a great relationship,” he said.

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

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,” said Carl Thayer, an expert on the South China Sea. “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 defense of Philippines sovereignty but regional security as well.”

Despite the difficult stage in the countries’ relations, Lorenzana remained optimistic that those ties would eventually bounce back.

“I think it’s just going through these bumps on the road,” Lorenzana told a news conference. “Relationships sometimes go to this stage … but over time it will be patched up.”