Kim Jong- un saw tools examination, states North Korean state media

Experts say Pyongyang is stepping up pressure against US after failed nuclear summit

North Korean state media has said leader Kim Jong-un find a live-fire drill of long-range multiple rocket launchers and unspecified tactical guided weapons. The admission came a day after South Korea's military seen North Korea launching several unidentified short-range bullets into the sea off its eastern coast.

Pyongyang's official Korean Central News Agency said Kim conveyed “great satisfaction” over Saturday's drills and was also emphasized that his frontline troops should keep a “high-alert posture” and enhance combat ability to” defend the political sovereignty and economic self-sustenance of the country “.

Earlier South Korea has issued a stern rebuke to Pyongyang for intensifying military tensions on the divided peninsula for firing what it called a series of” unidentified short-range bullets” into the sea.

The projectiles were fired on Saturday from the east coast city of Wonsan at around 9am, and flew 70 to 200 km towards the north-east, South Korea's Office of the Joint Chiefs of Staff said in a statement.

The launches were likely to be entailed as a warn to the US after the failure of a denuclearisation summit in Hanoi between North Korea's Kim Jong-un and the US president, Donald Trump, analysts said.

North Korea had wished to get US sanctions lifted at the February meeting, but Trump walked away, claiming that Pyongyang was not prepared to go far enough in dismantling its nuclear weapons programme.

Since then both leaders have said they are open to meeting again, and praised their personal relationship, but there has been little motion on key obstacles to a deal.

On Saturday Trump tweeted:” Anything in this very interesting world is possible, but I believe that Kim Jong Un fully realises the great economic potential of North Korea,& will do nothing to interfere or end it. He also knows that I am with him& does not want to break his promise to me. Deal will happen !”

Yang Uk, a senior research fellow at the Korea Defence and Security Forum, said Saturday's action was an expression of the North's frustration.” It is a message that[ North Korea] could return to the previous confrontational mode if there is no breakthrough in the stalemate ,” he told Reuters.

The bullets appeared to be fired from multiple rocket launchers and were not ballistic missiles, Reuters reported, quoting weapons experts. South Korea had initially said North Korea had launched missiles but later dedicated the more vague description.

In response to the firings, Seoul issued one of the strongest statements since the two countries launched a fresh round of reconciliation attempts last year.

” We are very concerned about the North's latest action ,” said South Korea, warning that North Korea had contravened a military agreement between the two states, and calling on it to” stop acts that intensify military tension on the Korean peninsula “.

The last North Korean missile launch was in November 2017, after a year of testing increasingly powerful weapons inspired belligerent responses from Trump, raising concerns about war.

Soon after, though, Pyongyang proclaimed its nuclear programme complete, then extended an olive branch to the US. It culminated in a first summit between Kim and Trump, which both sides declared a success.

Kim signed a joint statement committing to denuclearisation, but it was a vaguely worded commitment that the regime has built several times before over the past three decades.

Pyongyang has been reluctant to commit to further concrete steps, but with sanctions biting hard is pushing the US to offer economic relief.

On Tuesday the vice foreign minister warned of” undesired repercussions” for the US if it fails to present a new posture in talks by the end of the year. And in a summit with Russian president Vladimir Putin late last month, Kim issued a scarcely veiled advising to the US that the Korean peninsula could easily slide back into a country of hatred. Trump in turn has tried to recruit Putin to increase pressure on Kim to denuclearise.