North Korea is displaying its trademark defiance over new United Nations sanctions, imposed after its sixth and largest-ever nuclear test, and is vowing to redouble efforts to fight off what it says is the threat of a US invasion.
US President Donald Trump says the sanctions, unanimously agreed on Monday by the 15-member UN Security Council, are just a small step toward what is ultimately needed to rein in Pyongyang over its nuclear and missile programmes.
North Korea's Foreign Ministry says the resolutions are an infringement on its legitimate right to self-defence and aimed at "completely suffocating its state and people through full-scale economic blockade".
"The DPRK will redouble the efforts to increase its strength to safeguard the country's sovereignty and right to existence and to preserve peace and security of the region by establishing the practical equilibrium with the US," it said in a statement on Wednesday carried by the official KCNA news agency.
The Democratic People's Republic of Korea (DPRK) is North Korea's official name.
The statement echoed comments on Tuesday by DPRK's Ambassador to the United Nations in Geneva, Han Tae Song, who said Pyongyang was "ready to use a form of ultimate means".
"The forthcoming measures ... will make the US suffer the greatest pain it ever experienced in its history," Han said.
The North's Rodong Sinmun newspaper also accused South Korea of being Washington's "puppet", criticising Seoul's agreement with the US to amend an existing bilateral guideline that will now allow the South to use unlimited warhead payloads on its missiles.
The UN Security Council agreed to tighten sanctions on North Korea, banning its textile exports and capping fuel supplies, and making it illegal for foreign firms to form commercial joint ventures with North Korean entities.
The UN resolution was triggered by North Korea's test of what it said was a hydrogen bomb.
Damage to mountainous terrain at the North's nuclear test site in Punggye-ri seen in satellite imagery taken after the latest test was more extensive than anything seen after the five previous tests, said 38 North, a Washington-based project which monitors North Korea, adding there's been activity at another location in the Mount Mantap site involving large vehicles and mining equipment.
The North accuses the US, which has 28,500 troops in South Korea, a legacy of the 1950-53 Korean War, of continual plans for invasion.
North Korea has also tested a missile capable of reaching the US, but experts say it is likely to be at least a year before it can field an operational nuclear missile that could threaten the US mainland.
Trump has vowed not to allow that to happen.
A tougher initial US draft resolution was weakened to win the support of China and Russia, both of which hold veto power on the UN Security Council.
"We think it's just another very small step, not a big deal," Trump told reporters at the start of a Tuesday meeting with Malaysian Prime Minister Najib Razak.
"I don't know if it has any impact, but certainly it was nice to get a 15-to-nothing vote, but those sanctions are nothing compared to what ultimately will have to happen."