South Korea's president ordered the military on Wednesday to "promptly and sternly" retaliate in the case of any North Korean provocation amid concerns Kim Jong-un could conduct the first nuclear test in five years.
Yoon Suk-yeol, who took office in May, presided over his first meeting with top military commanders and called for strong capabilities to deter North Korea's nuclear and missile programmes, the presidential office said.
North Korea has this year been conducting missile tests at an unprecedented pace and is believed to be preparing for its seventh nuclear test.
The military meeting took place a day after US Air Force F-35A stealth fighters arrived in South Korea on their first publicly announced visit since 2017 as the allies and the nuclear-armed North engage in an escalating cycle of displays of weapons.
"President Yoon said strong defence capabilities should be ready to protect the country's security and national interest as the security uncertainties surrounding South Korea and Northeast Asia are growing more than ever," his presidential office said.
Last week, Yoon met with US President Joe Biden and Japanese Prime Minister Fumio Kishida on the sidelines of the NATO summit in Madrid.
Biden agreed to explore further means to reinforce "extended deterrence" against North Korea.
Over the weekend, North Korea criticised the United States, South Korea and Japan's recent agreement on strengthening military cooperation to be a means to materialise a US plan for a military alliance like NATO in the region.
North Korea's foreign ministry spokesperson said as much to a question put by KCNA, the state news agency reported on Sunday.
"The reality clearly shows that the real purpose of the US spreading the rumour about 'threat from North Korea' is to provide an excuse for attaining military supremacy over the Asia-Pacific region," said the spokesperson.
"The prevailing situation more urgently calls for building up the country's defences to actively cope with the rapid aggravation of the security environment," the spokesperson added.
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