Kim Jong Un
Kim Jong Un Reuters

North Korean leader Kim Jong Un on Tuesday vowed to continue developing his country’s nuclear deterrent and introduce a “new strategic weapon” in 2020.

In his annual New Year’s address, Kim said there was “no ground” for Pyongyang to maintain the moratorium on missile tests, with the country set to continue developing strategic weapons unless the US gave up its hostile approach.

He also threatened that the US would "suffer helplessly" if there continued to be delays in talks aimed at dismantling his country’s nuclear and missile programs.

Kim’s comments came after the US missed his deadline of December 31 to ease the sanctions that have been imposed on the isolated country.

North Korea has threatened to take unspecified action if US sanctions are not eased, and speculation has centered on the possibility of a new missile test, possibly of an intercontinental ballistic missile capable of delivering a nuclear warhead.

On Saturday, Kim convened a key meeting of top ruling party officials ahead of the deadline to the US.

A day later, US President Donald Trump's national security adviser, Robert O’Brien, warned the North Korean leader against conducting a ballistic missile test.

"If Kim Jong Un takes that approach, we will be extraordinarily disappointed, and we will demonstrate that disappointment," he stressed in a television interview.

Kim and Trump engaged in months of mutual insults and threats of devastation in 2017, sending tensions soaring before a diplomatic rapprochement the following year.

The pair have met three times since June 2018, most recently in Vietnam in February, but with little progress towards denuclearization. Pyongyang has set Washington a December 31 deadline to make new concessions to kickstart stalled talks.

Since that June meeting, North Korea has conducted several tests of ballistic missiles.

Trump warned recently that Kim had "everything" to lose through hostility towards the United States.