MANILA - The Philippines is looking into Washington's call to downgrade diplomatic ties with North Korea, but suspending the reclusive state from a regional security forum would be a "very hard decision," Manila's chief envoy said Friday.

"The less we talk, the more grave the situation can become," said Foreign Secretary Alan Peter Cayetano, who will host fellow ministers from the 27-nation ASEAN Regional Forum (ARF) here on Monday.

The meeting will allow countries such as the US to confront North Korea over its missiles tests despite UN Security Council resolutions.

Washington wants to add pressure on North Korea by asking countries to scale down diplomatic exchanges with Pyongyang and seeking its suspension from the ARF, which includes four other nations in the aborted Six Party Talks.

"We are studying how we can downgrade because we don't have much engagement with them," Cayetano told reporters.

Cayetano was set to meet with some foreign ministers Friday night to "align ourselves" on issues such as Washington's suspension call.

"It would be more prudent to consult all of the members and I predict there will be two sides to it," he said.

PEACE MAKER

Cayetano cited concerns that "it's time to make a stand" and inform North Korea it could not continue to engage with ARF nations unless it stopped its missile tests.

But he noted that the ARF was the only forum where North Korea was a participant, and could be a venue for continuing discussions. Pyongyang has been been with the ARF since 2000.

"It's a very difficult decision," Cayetano said.

He said there was also a need to look into concerns of Pyongyang "which feels that their existence, their security, their regime" were "threatened."

"But what we're saying is that you will not get us to talk about your security if you just continue testing those missiles," he said. "You don't threaten us to get us to the table."

The Philippines tried to play "peace maker" with North Korea following a request from US President Donald Trump to President Rodrigo Duterte, Cayetano said.

Pyongyang's deputy foreign minister earlier visited Manila ahead of the regional forum, amid concerns over his country's latest intercontinental ballistic missile tests.

Cayetano said the Philippines "strongly communicated" ASEAN's stand on the Korean Peninsula conflict "but we also listened."