South Korea said it was keeping close tabs on the North amid speculations that it could fire ballistic missiles at any time

North Korea’s state media marked the nation’s founding anniversary on Saturday with calls for a nuclear arms buildup, in defiance of mounting international sanctions.

South Korea’s military said it was keeping close tabs on the North amid speculation it could stage a missile launch or another nuclear test to mark the 1948 establishment of the Democratic People’s Republic of Korea.

North Korea conducted its fifth nuclear test on September 9 last year, and then carried out a sixth a week ago, saying it was a hydrogen bomb that could be fitted onto a missile — prompting global condemnation and calls for further sanctions.

Self-reliance

In July, it tested two intercontinental ballistic missiles (ICBMs) that appeared to bring much of the mainland U.S. into range. “The defence sector, in step with the party’s Byungjin policy (of developing the economy and nuclear weapons at the same time) must make cutting-edge Juche weapons in greater quantities,” the Rodong Sinmun said in an editorial, referring to the national philosophy of “Juche” or self-reliance. The mouthpiece of the North’s ruling party called for more “miracle-like events” such as the two ICBM tests to deter the United States which it said was bent on “decapitating” the nation’s leader Kim Jong-Un.

“No matter how the U.S. and its puppets kick up a ruckus, our republic, which has a strong military and the most powerful Juche bombs and weapons, and whose territory has all turned into fortresses, and all its people armed to the teeth, will remain an eternal iron-clad citadel,” it said.

In another commentary, Rodong Sinmun said the U.S. would continue receiving “gift packages in different shapes and sizes” as long as it sticks to what it said was a hostile policy against the North.

‘Gift packages’

Mr. Kim himself has called the ICBM tests “gift packages” that the North was delivering to the “U.S. bastards”. A South Korean defence ministry spokesman said there were no signs of the North preparing a missile launch or a nuclear test on Saturday. “The military is maintaining its utmost defence posture, keeping a close watch over the North. But there is nothing out of the ordinary,” he told AFP. But he warned that the North could fire ballistic missiles at any time from easily concealed mobile launchers.

South Korea’s Yonhap news agency quoted an unidentified government official as saying that the North could carry out a seventh nuclear test at its Punggye-ri test site at any moment. The official also said the North could choose the founding anniversary of the ruling Workers’ Party, which falls on October 10, to hold another test.

Meanwhile, two Japanese fighters and two U.S. bombers carried out a joint exercise over the East China Sea on Saturday, Defence Minister Itsunori Onodera said in Tokyo. “It is important for us to display strong Japan-U.S. relations for Japan’s security,” Mr. Onodera said.

The U.S. wants the UN Security Council to vote on Monday to impose tougher sanctions against North Korea despite resistance from China and Russia. A U.S.-presented draft resolution calls for an oil embargo on North Korea, an assets freeze on Mr. Kim, a ban on textiles and an end to payments of North Korean guest workers.

Diplomatic sources said Russia and China opposed the measures as a whole, except for the ban of textiles, during a meeting of experts Friday.