Kathmandu. North Korean leader Kim Jong-un’s influential sister, Kim Yo Jong, has warned that joint military drills between South Korea and the United States could have “unimaginably catastrophic consequences”.

In a statement released on Tuesday, he described the annual military exercises being conducted by Seoul and Washington as a “serious provocation” that would lead to further tensions on the Korean Peninsula.

South Korea and the United States began their spring military exercises “Freedom Shield” on Monday. The exercise will continue till March 19. About 18,000 South Korean troops are expected to take part, but the number of U.S. troops has not been disclosed.

The nuclear-armed North Korea, which invaded neighboring South Korea in 1950 and launched the Korean War, has long blamed the joint drills as a preparatory exercise for an invasion of the country.

Kim Yo Jong’s statement was quoted by Pyongyang-based state Korean Central News Agency (KCNA). He warned that such exercises could lead to “unimaginably catastrophic consequences”, and could further destabilise regional security.

He was recently promoted to head of the general affairs department of North Korea’s ruling Workers’ Party. Analysts see this post as an impressive responsibility similar to that of the party’s general secretary.

His comments came after his brother Kim Jong Un dismissed Seoul’s recent peace initiatives as “incoherent, misguided farces”. He also said North Korea had “no business dealings” with South Korea.

Kim Yo Jong Un has described the joint military exercises as a step at a sensitive time of global instability. According to him, the global security architecture is rapidly weakening and the incidents of war are increasing in various areas.

He blamed the current situation for the “reckless act of international miscreants”. Pyongyang also strongly condemned the recent attacks on Iran by the US and Israel as “illegal attacks”. North Korea said the incident exposed America’s “evil nature”.

North Korea and the United States have been at loggerheads politically and militarily for decades. However, in recent months there have been signs that Washington is pushing to resume high-level talks with Pyongyang.

Some reports and analysts have also pointed to a possible summit between US President Donald Trump and North Korean leader Kim Jong Un later this year.

Kim Jong Un, who has long ignored those proposals, said last month that if Washington accepted North Korea’s nuclear status, the two countries could “live together”.