North Korea yesterday angrily insisted tough new United Nations sanctions would not stop it from developing its nuclear arsenal - and warned it would not negotiate while being threatened by the United States.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 US$1 billion (HK$7.8 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 yesterday 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.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.