North Korea fired a ballistic missile into the sea on Tuesday in a continuation of its recent weapons tests, the South Korean and Japanese militaries said, hours after the U.S. reaffirmed its offer to resume diplomacy on the North’s nuclear weapons program.

The South’s Joint Chiefs of Staff didn’t immediately say what kind of ballistic missile it was or how far it flew. Japan's coast guard issued a maritime safety advisory to ships but didn't immediately know where the weapon landed.

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South Korea’s presidential office was planning to hold a national security council meeting to discuss the launch. A strong South Korean response could anger North Korea, which has been accusing Seoul of hypocrisy for criticizing the North's weapons tests while expanding its own conventional military capabilities.

Ending a monthslong lull in September, North Korea has been ramping up its weapons tests while making conditional peace offers to Seoul, reviving a pattern of pressuring South Korea to try to get what it wants from the United States.

Within days, President Joe Biden’s special envoy for North Korea, Sung Kim, is schedule to hold talks with U.S. allies in Seoul over the prospects of reviving talks with North Korea.

Read:UN meets on North Korea missile test which Europeans condemn

Nuclear negotiations between Washington and Pyongyang have stalled for more than two years over disagreements in exchanging the release of crippling U.S.-led sanctions against North Korea and the North’s denuclearization steps.

North Korean leader Kim Jong Un has vowed to strengthen his nuclear deterrent since his diplomatic fallout with then-President Donald Trump.

His government has so far rejected the Biden administration’s offers to restart dialogue without preconditions, saying that Washington must first abandon its “hostile policy,” a term the North mainly uses to refer to sanctions and U.S.-South Korea military exercises.

But while North Korea is apparently trying to use South Korea’s desire for inter-Korean engagement to extract concessions from Washington, analysts say Seoul has little wiggle room as the Biden administration is intent on keeping sanctions in place until the North makes concrete steps toward denuclearization.

“The US continues to reach out to Pyongyang to restart dialogue. Our intent remains the same. We harbor no hostile intent toward the DPRK and we are open to meeting without preconditions,” Sung Kim told reporters on Monday, referring to the North’s official name, the Democratic People’s Republic of Korea.

“Even as we remain open to dialogue, we also have a responsibility to implement the U.N. Security Council resolutions addressing the DPRK,” he said.

Last week, Kim Jong Un reviewed powerful missiles designed to launch nuclear strikes on the U.S. mainland during a military exhibition and vowed to build an “invincible” military to cope with what he called persistent U.S. hostility. Earlier, Kim dismissed U.S. offers for resuming talks without preconditions as a “cunning” attempt to conceal its hostile policy on the North.

The country has tested various weapons over the past month, including a new cruise missile that could potentially carry nuclear warheads, a rail-launched ballistic system, a developmental hypersonic missile and a new anti-aircraft missile. The test of the hypersonic missile on Sept. 28 came shortly before North Korean Ambassador Kim Song called for the Biden administration to permanently end joint military exercises with South Korea and the deployment of strategic military assets to the region in his speech to the U.N. General Assembly.

The North in recent weeks has also restored communication lines with the South and said it could take further steps to improve bilateral relations if Seoul abandons its “double-dealing attitude” and “hostile viewpoint" over its weapons development.

Some outside experts say North Korea aims to pressure South Korea not to criticize its ballistic missile tests, which are banned by U.N. Security Council resolutions, as part of its efforts to win international recognition as a nuclear power.