Resistant North Korea rejects talks and says 'Violent violation of our sovereignty' after new sanctions.

North Korea vowed Monday that tough new United Nations sanctions would not stop it from developing its nuclear arsenal, as it rejected talks and angrily warned the United States of retaliation.

The message of defiance was the first major response to the US-drafted sanctions that the UN Security Council unanimously approved over the weekend that could cost North Korea $1 billion a year while restricting crucial economic links with China.

The sanctions were a "violent violation of our sovereignty", Pyongyang said in a statement carried by its official Korea Central News Agency.

"We will not put our self-defensive nuclear deterrent on the negotiating table" while it faced threats from Washington, it said, "and will never take a single step back from strengthening our nuclear might".

North Korea threatened to make the United States "pay the price for its crime... thousands of times".

The statement came as North Korea's Foreign Minister Ri Yong-Ho was in the Philippine capital of Manila for a security forum with the top diplomats from the United States, China, Russia and other Asia-Pacific nations.

US Secretary of State Rex Tillerson on Monday ruled out a quick return to dialogue with North Korea, saying the new sanctions showed the world had run out of patience with Pyongyang's nuclear weapons ambitions.

Speaking to reporters at the forum, Tillerson said Washington would only consider talks if Pyongyang halted its ballistic missile programme.

"The best signal that North Korea could send that they're prepared to talk would be to stop these missile launches," he said.

Tillerson held out the prospect of US envoys at some point sitting down with Pyongyang's isolated regime and avoiding war, although he refused to say how long the North might have to refrain from testing more long-range missiles.

"I'm not going to give someone a specific number of days or weeks. This is really about the spirit of these talks," he said.

The sanctions were in response to the North conducting its first two intercontinental ballistic missile tests last month that Kim boasted showed he could strike any part of the United States.

- A rare exchange -

Tillerson's remarks followed a rare exchange on Sunday between Ri and his South Korean counterpart, Kang Kyung-Wha, at a dinner to welcome all the foreign ministers.

Kang urged Ri to accept Seoul's offers of military talks to lower tensions on the divided peninsula and for discussions on a new round of reunions for divided families, according to South Korea's Yonhap news agency.

But Yonhap reported that Ri retorted: "Given the current situation in which the South collaborates with the US to heap pressure on the North, such proposals lacked sincerity".

US President Donald Trump and his South Korean counterpart, Moon Jae-In, spoke on the phone on Sunday and agreed the North "poses a grave and growing direct threat", according to a White House statement.

Trump later took to social media to hail the vote, thanking Russia and China in a Twitter post for backing the sanctions that either could have halted with their UN veto.

Trump said he was "very happy and impressed with 15-0 United Nations vote on North Korea sanctions".

Tillerson, who held separate talks in Manila with foreign ministers Wang Yi of China and Sergei Lavrov of Russia on Sunday, also sought to emphasise a united stance against the North.

"It's quite clear in terms of there being no daylight between the international community as to the expectation that North Korea will take steps to achieve all of my objectives, which is a denuclearised Korean peninsula," he said.

In pointed criticism of Beijing and Moscow, Pyongyang's fiery statement said other nations that "received appreciation from the US" for supporting the resolution would also be "held accountable for escalating tension on the peninsula."

Washington has recently stepped up pressure on Beijing to rein in its unpredictable neighbour, which relies heavily on China for aid and trade.

Signalling that differences remained between the world powers on how to handle the North, Wang on Sunday reiterated China's position that sanctions alone would not solve the problem and called again for the US to talk to the North.