North Korea fired off two “unidentified projectiles” from the country’s west, toward the Sea of Japan on Tuesday, the South Korean military said, just hours after the nation offered to resume nuclear talks with the United States and a day ahead of a key Cabinet reshuffle in Japan.

The South’s military said the two “short-range” projectiles that flew about 330 kilometers across the peninsula from near Gaechon, South Pyongan province, had reached a maximum altitude of around 50 km to 60 km. South Korean and U.S. intelligence authorities were analyzing the exact type of weapons fired, the South’s Joint Chiefs of Staff said in a statement.

“Our military is monitoring the situation in case of additional launches and maintaining a readiness posture,” it added.

Japan’s Defense Ministry said the launches posed no immediate threat to the country’s security and did not land in Japanese territory or its exclusive economic zone.

The launches, the North’s eighth volley of tests since late July and its 18th and 19th weapons tests this year, come amid growing concerns in Tokyo that the North has been working hard to develop powerful new weapons systems, including short-range ballistic missiles capable of striking as far as even Japan.

RELATED STORIES Japan's budget on North Korea goes unused amid stalled abduction talks

Defense Minister Takeshi Iwaya said in Tokyo that North Korea, through its repeated launches, has been working strenuously to bolster its weapons and ballistic missile technology.

Pyongyang is banned from the use of all ballistic missile technology under United Nations sanctions resolutions.

“We view this as a very serious issue, and we want to keep close tabs on the situation while making every effort to stay vigilant” of the North Korean nuclear threat, Iwaya said at a televised news briefing.

The North’s saber-rattling comes a day before Prime Minister Shinzo Abe is due to reshuffle his Cabinet, a move that could see him change up key posts, including the defense and foreign ministerial portfolios. Both posts have had significant dealings with the North’s nuclear weapons program.

Pyongyang had said earlier Tuesday that it was willing to restart nuclear talks with the U.S. later this month, but warned that chances of a deal could end unless Washington takes a fresh approach.

In a statement carried by the North’s official Korean Central News Agency, Vice Foreign Minister Choe Son Hui said Pyongyang was willing to have “comprehensive discussions” with the United States in late September at a time and place to be agreed to between both sides.

Her offer comes after North Korean leader Kim Jong Un agreed in a June 30 meeting with U.S. President Donald Trump to reopen working-level talks stalled since their failed February summit in Hanoi.

Andrew O’Neil, an expert on North Korea and a professor at Griffith University in Australia, said Pyongyang was likely using the dual-pronged approach to pressure the U.S. ahead of any return to the negotiating table.

“My sense is that Pyongyang is very much looking to drive home what it sees as a tactical advantage in current dealings with the U.S. — that is, a U.S. president who is inclined to make short-term concessions for a possible long-term commitment from the North,” he said.

Trump, asked about the offer at the White House, repeated that he maintains a “good relationship” with Kim.

“I just saw it as I’m coming out here, that they would like to meet. We’ll see what happens,” Trump said. “I always say having meetings is a good thing, not a bad thing.”

A senior Trump administration official told The Japan Times that it was “aware of the reports of projectiles launched from North Korea.”

“We are continuing to monitor the situation and consulting closely with our allies in the region,” the official said.

At a televised news conference, Japanese Chief Cabinet Secretary Yoshihide Suga said that information exchanges with Seoul were continuing, despite the two neighbors ongoing trade and history row and South Korea’s decision last month to abandon a key military intelligence-sharing pact with Japan.

“Japan and South Korea are maintaining tight contact over the North Korean situation, including on the string of launches,” Suga, the government’s top spokesman, said.

South Korea’s Yonhap news agency, however, said that Tokyo had not asked Seoul to share intelligence on the latest firings, though Yonhap said Japan had made such a request after the North’s previous test on Aug. 24. It did not say where it got this information.

On Sunday, U.S. Secretary of State Mike Pompeo said he hoped for a return to denuclearization talks in the coming days or weeks, while reiterating the U.S. objective of North Korea’s complete denuclearization and adding that Washington was disappointed by North Korea’s recent volley of short-range missile tests.

In her statement, Choe stressed that Washington needed to present a new approach — or the talks could again fall apart.

“I believe that the U.S. side will come out with a proposal geared to the interests of the DPRK and the U.S. and based on the calculation method acceptable to us,” Choe said.

“If the U.S. side fingers again the worn-out scenario which has nothing to do with the new calculation method at the DPRK-U.S. working negotiation to be held with so much effort, the DPRK-U.S. dealings may come to an end,” she said, using the acronym for the North’s formal name, the Democratic People’s Republic of Korea.

In April, Kim set a year-end deadline for the United States to show more flexibility in talks, which broke down in Hanoi in February over U.S. demands for North Korea to relinquish its nuclear arsenal and Pyongyang’s demands for relief from crushing U.N. sanctions.

In a speech Friday, the U.S. envoy for North Korea said the Trump administration is prepared to negotiate whenever the Kim regime is ready.

“We have made clear to North Korea we are prepared to engage as soon as we hear from them,” Stephen Biegun, the special representative for North Korea talks, said in a live-streamed speech at the University of Michigan. “We are ready, but we cannot do this by ourselves.”

Biegun also pointed to the risks of allowing Pyongyang to continue to possess its nuclear arsenal and the effects such a scenario would have on the region.

“While a number of countries and economies in Asia have the scientific wherewithal and technical capability to develop nuclear weapons, they have made the judgment that possessing such weapons creates more risk than security for their people,” he said.

“Allies such as Japan and South Korea have forsworn nuclear weapons programs in part because they trust the protection of extended nuclear deterrence that is included in their alliances with the United States,” Biegun added. “But how long will this conviction hold if such arms are a mere short-range ballistic missile flight away from their territory? At what point will voices in South Korea or Japan, and elsewhere in Asia, begin to ask if they need to reconsider their own nuclear capabilities?”