People watch a television news screen showing file footage of a Democratic People's Republic of Korea's missile launch, at a railway station in Seoul on Sept 10, 2019. The DPRK on Sept 10, 2019 fired projectiles toward the sea, Republic of Korea's military said, hours after Pyongyang said it is willing to hold working-level talks with the United States in late September. (JUNG YEON-JE / AFP)

SEOUL - The Democratic People's Republic of Korea (DPRK) fired a new round of short-range projectiles on Tuesday, Republic of Korea (ROK) officials said, only hours after it signalled a new willingness to resume stalled denuclearisation talks with the United States.

The launches came hours after a statement by Vice-Foreign Minister Choe Son Hui in state media that DPRK was willing to have "comprehensive discussions" with the US in late September at a time and place to be agreed

The launches were detected early on Tuesday morning by the ROK military, which said they appeared to be short-range projectiles.

The launches came hours after a statement by Vice-Foreign Minister Choe Son-hui in state media that DPRK was willing to have "comprehensive discussions" with the US in late September at a time and place to be agreed.

Choe warned that Washington needed to present a new approach or the talks could fall apart again. A US State Department spokeswoman said on Monday she did not have any talks to announce at that time.

Hours later, ROK's foreign ministry announced that Seoul's nuclear envoy had held phone talks with his US counterpart Tuesday, reports Xinhua.

Lee Do-hoon, ROK's special representative for Korean Peninsula peace and security affairs, talked over phone with Stephen Biegun, US special representative for the Democratic People's Republic of Korea (DPRK) affairs.

During the phone conversation, the nuclear envoys discussed recent developments on the peninsula and actual measures for complete denuclearization and permanent peace, the ministry said. The two diplomats agreed to meet in the near future for further consultations.

Shares of ROK construction firms with exposure to ROK surged after the announcement that DPRK was willing to restart talks with the US, and continued to gain despite the latest projectile launches.

US President Donald Trump and DPRK leader Kim Jong-un met at the demilitarised zone (DMZ) between the two Koreas in June and agreed to restart working-level negotiations that had been stalled since an unsuccessful second summit between the two leaders in Hanoi in February.

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Since the DMZ meeting, however, American officials said their attempts to resume talks had gone unanswered. DPRK has also conducted at least eight launches since then, usually with multiple missiles each time.

"All of these acts by North Korea that escalate tensions do not help efforts to ease tension on the Korean peninsula, and we reiterate our calls for an immediate halt," ROK's Joint Chiefs of Staff said in a statement.

The DPRK is also referred to as North Korea. 

An AFP graphic shows a map of the Democratic People's Republic of Korea where "unidentifiable projectiles" were launched on Sept 10, 2019.

Simple answer? 

While analysts said DPRK conducts missile tests for a range of purposes, including technical development and reassurance for the defence establishment, Tuesday's launches appeared to have been timed to send a message to Washington.

The launches were probably the latest case of Kim turning to missile tests as diplomatic signalling, said Daniel DePetris, a fellow at Defense Priorities, a Washington-based think tank.

"Far be it from me to get inside Kim's head, but the simplest answer may be the most accurate: North Korea is demonstrating what will happen if the US doesn't come to the table with realistic proposals," he said.

Trump has played down previous tests this year, saying he did not believe short-range missiles violate any agreements.

Other officials, including Trump's national security adviser John Bolton, have said even short-range launches by DPRK are banned under United Nations resolutions.

READ MORE: DPRK fires more projectiles, rules out talks with ROK

Separately, DPRK declared last year a self-imposed moratorium on tests of nuclear weapons as well as launches of its long-range intermediate and intercontinental ballistic

missiles.

The missiles unveiled this year have all been short-range, but analysts warn they show significant technological advances and could be used to evade missile defences.

The DPRK has said its development of new weapons aims to counter military threats and offensive pressures against its security, including joint drills by the US and ROK.

While the missiles unveiled this year have been short-range, analysts warn they have shown significant technological advances and could be used to evade missile defences.