US President Donald Trump said on Monday that he would be disappointed if something is “in the works” in North Korea.

At the White House when asked about the situation, Trump said, “We’ll see. I’d be disappointed if something would be in the works. And if it is, we’ll take care of it”.

Trump further said, “We’re watching it very closely.”

The nuclear-armed North has issued increasingly strident declarations in recent weeks, even promising an ominous “Christmas gift” if Washington does not come up with some concessions.

Trump’s remarks came days after Pyongyang carried out two “important tests” at its Sohae Satellite Launching Ground on December 7 and 13.

The North Korea’s Academy of Defense Science said in a statement, carried Saturday by the official Korean Central News Agency (KCNA), that “the research successes being registered by us in defense science one after another recently will be applied to further bolster up the reliable strategic nuclear deterrent”.

On Saturday, North Korea carried out “another crucial test” at its satellite launch site and the results would be used to strengthen its “reliable strategic nuclear deterrent”.

Last month, North Korea launched two “unidentified projectiles” on the Thanksgiving holiday in the US as nuclear talks between Pyongyang and Washington remain deadlocked.

Earlier in November, North Korea had carried out a “successful” new test of its “super-larger multiple rocket launcher” system, the latest in a series of provocations by Pyongyang.

In August this year, North Korea fired two unidentified projectiles into the East Sea.

During the 10-day training, North Korea raised tensions with its own missile and other weapons tests. But North Korea’s typical harsh rhetoric over the drills largely focused on South Korea, not the United States, in a suggestion that it’s still interested in resuming nuclear talks with the US.

North Korea is under multiple sets of international sanctions over its nuclear weapon and ballistic missile programmes and lifting some of them was a key demand at the Hanoi summit.

The two leaders met again in late February in the Vietnamese capital of Hanoi, but the second DPRK-US summit ended without any agreement. Under the Singapore deal, Kim and Trump agreed to the complete denuclearisation of and the peace settlement in the peninsula.

(With inputs from agency)