MANILA - US President Donald Trump will press nations attending a summit in the Philippines next month to "take unilateral steps" against the nuclear threat posed by North Korea, senior White House officials said Tuesday.

Trump will meet with Philippine President Rodrigo Duterte and other leaders who will take part in the East Asia Summit in Manila in November.

"There are a number of steps that countries have taken in the wake of the United Nations Security Council resolutions that have been passed successively earlier this year, including the one last month," a senior White House official said in a telephone conference with international media.

"What we're looking for is for countries to fully implement those resolutions but also to look at other ways to bilaterally take unilateral steps against North Korea, to expel North Korea workers, to shut down North Korea businesses and other fronts in their countries that serve to funnel cash back to the regime, to downgrade or even end their diplomatic relations with North Korea."

Last week, the Australian parliament received a copy of North Korean leader Kim Jong-un's letter to a number of parliaments declaring itself a "full-fledged nuclear power" and accusing Trump of "trying to drive the world into a horrible nuclear disaster."

Senior White House officials called the letter "desperate."

"The letter from the North Korean regime, to our minds, is a sign the international pressure campaign against North Korea is having the effects that we would want it to have," an official said.

"It is increasing their sense of diplomatic isolation, it is constraining their ability to generate cash for their programs building missiles and nuclear devices, and I think it's a sign of desperation on the part of Kim that he's sending letters like that."

Trump will also meet with Australian Prime Minister Malcolm Turnbull during his visit in Manila.

Pyongyang has undertaken an unprecedented missile testing program in recent months, as well as its biggest nuclear test yet in early September, angering its only major ally China and drawing further sanctions from the UN and US.

• If threatened, US will 'totally destroy' North Korea, Trump vows

North Korea stoked tensions again last week when it reiterated a threat to conduct an atmospheric nuclear test over the Pacific Ocean in a demonstration of its nuclear capability. With Reuters