North Korean leader Kim Jong-un may announce the suspension of nuclear talks with the United States when he delivers his New Year's Day address or holds a key meeting of the ruling Workers' Party later this month, an expert said Friday.

Sung Ki-young, a senior researcher at the Institute for National Security Strategy made the remarks during a North Korea forum organized for foreign diplomats amid heightened concerns Kim could put his threat to take a "new way" into action.

The North's leader gave the United States until the end of this year to come up with a new negotiating proposal satisfying Pyongyang's demands, strongly suggesting that otherwise, he could restart tests of nuclear weapons or intercontinental ballistic missiles.

"In the New Year's address or the party meeting, probably Kim Jong-un may announce the suspension of nuclear talks with President Trump and unveil what on earth the new way will mean," the expert said during the forum attended by diplomats from 23 countries.

Kim is expected to deliver his New Year's address on Jan. 1 as he has done so in previous years. But it is unclear when the plenary meeting of the central committee of the Workers' Party will be held because the North has only said it will be held later this month without giving a specific date.

Sung said that the North is unlikely to announce any big decisions before the party meeting or the New Year's address because that would overshadow the key events.

Nuclear negotiations have made little progress since February's summit between US President Donald Trump and North Korean leader Kim Jong-un in Hanoi ended without an agreement.

Tensions have since escalated as the North has tested a series of new weapons this year, including a super-large multiple rocket launcher and a submarine-launched ballistic missile, and more recently, two "important" tests of what appeared to be engines for a long-range rocket or an intercontinental ballistic missile earlier this month. (Yonhap)