North Korea on Saturday (September 16) lambasted the U.S. at the Non-Aligned Movement summit in Havana - vowing never to return to nuclear talks if sanctions against it weren't lifted. Washington is looking to put more pressure on Pyongyang following the communist state's launch of a barrage of missiles in July and Pyongyang's refusal to return to six-country nuclear talks for almost a year. North Korea's nominal number two leader, Kim Yong-nam, told a session of the NAM summit on Saturday that the U.S. would have to lift sanctions if it wanted North Korea to return to the negotiating table. "Such being the case, there is no justification whatsoever to urge the DPRK to return to the talks unconditionally. The DPRK will never go back to the talks under the U.S. sanctions," said Kim in an address to the NAM summit. On Friday (September 15) North Korean warned South Korea against joining U.S. sanctions. A U.N. Security Council resolution passed in July after the North's missile launches called on member states to stop trade and financial transactions with the North. The U.S. has also cracked down on North Korea's finances. North Korea has said it regards sanctions against it as a declaration of war. "Now it is clear to everyone that the nuclear issue of the DPRK and the U.S. will be resolved eventually, only when the U.S. respects the DPRK's sovereignty and right to choose, and changes its hostile policy into a peaceful coexistence policy and fundamentally eliminates all of U.S. nuclear weapons and the danger of nuclear war in and around the Korean peninsula," said Kim. "The United States deadly bent on its hostile policy against the DPRK as ever is escalating all sorts of sinister manoeuvres by designating the latter as part of an axis of evil and target of pre-emptive nuclear strikes," said Kim. Under U.S. measures, such as the freezing of North Korean bank accounts and warnings on financial institutions helping the North . Communist North Korea, whose official name is the Democratic People's Republic of Korea, has boycotted talks among the two Koreas, China, Japan, Russia and the United States since November. Kim, who heads North Korea's parliament, is the first senior Pyongyang official to make public comments since U.S. President George W. Bush and South Korean President Roh Moo-hyun met in Washington on Thursday and called on the North to return to talks. The United States has repeatedly called on the North to return to the table and implement a deal reached in September 2005 under which Pyongyang agreed to scrap its nuclear weapons programs in return for aid and security assurances. North Korea is believed to have enough nuclear material to build as many as a dozen nuclear bombs, but it has never tested one.