North Korea slammed the United States over a recent Pentagon report that labelled it a “persistent” threat because of weapons of mass destruction, saying it will counter any US aggression or provocations with “the most overwhelming and sustained response strategy.”

Last week, the Pentagon released the unclassified version of its “2023 Strategy for Countering Weapons of Mass Destruction” describing WMD challenges and methods to address them.

The report stated that while China and Russia present “the principal WMD challenges,” North Korea, Iran and violent extremist organisations remain “persistent regional threats” that must also be addressed.

Such US descriptions of North Korea and the North’s angry response aren’t unusual. But the latest exchange comes as concerns grow that North Korea is pushing for a weapons transfer deal with Russia in violation of UN Security Council resolutions.

“The US has just revealed its dangerous intention for aggression to seriously violate the sovereignty and security of (North Korea) and other independent sovereign states by threatening them with WMDs, and realize its wild ambition for seizing global military hegemony,” an unidentified spokesperson for North Korea’s Defence Ministry said in a statement carried by state media.

North Korea’s military will “counter the US imperialist aggressor’s military strategy and provocations with the most overwhelming and sustained response strategy,” the statement said.

North Korea’s nuclear programme has taken on new urgency since it enacted a law last year that authorises pre-emptive use of nuclear weapons.

Since the beginning of 2022, North Korea has conducted more than 100 missile tests, many of them involving nuclear-capable weapons potentially able to target the US and South Korea.

Last week, North Korea’s parliament amended the country’s constitution to include the nuclear law, an indication that the North is further boosting its nuclear doctrine.

During the parliament meeting, leader Kim Jong Un called for an exponential increase in the production of nuclear weapons and for his country to play a larger role in a coalition of nations confronting the United States in a “new Cold War.”

South Korea’s Defence Ministry warned in a statement on Wednesday that any attempt by North Korea to use nuclear weapons would result in the end of the Kim government. It said North Korea’s inclusion of the nuclear law in its constitution will further deepen its international isolation and the suffering of its people.

The Pentagon report cited the North Korean nuclear law in explaining its security threat. The report said North Korea is developing mobile nuclear capabilities that place the US homeland and regional allies and partners at risk.

The report also said North Korea maintains up to several thousand metric tons of chemical warfare agents and the capability to produce nerve, blister, and choking agents. It said North Korea’s potential chemical deployment methods include artillery, ballistic missiles, and unconventional forces.

The US and South Korea have been responding to North Korea’s advancing nuclear arsenal with expanded joint military exercises and temporary deployments of US long-range bombers and a nuclear-armed submarine. North Korea calls such moves grave provocations that force it to further strengthen its nuclear programme.

North Korea’s Defence Ministry said in the statement that the term “persistent threat” is more suitable for the US, citing its intensifying military drills with South Korea and the deployment of the nuclear-armed submarine that it said carried weapons “large enough to totally destroy one state.”

In September, Kim travelled to Russia’s far eastern region to meet with President Vladimir Putin and visit key military sites. North Korea and Russia said the trip was meant to boost their cooperation but neither side disclosed details.

Foreign officials and experts believe North Korea hopes to obtain advanced Russian technologies to help it develop spy satellites, nuclear-propelled submarines and powerful long-range missiles in return for supplying Russia with conventional arms exhausted by its war with Ukraine.