SEOUL, South Korea -- North Korea sent sharply mixed messages Saturday, vowing to "smash U.S. nuclear maniacs" in a "holy war" while its diplomats told New Mexico Gov. Bill Richardson their country had no intention of building nuclear bombs.
Pyongyang's belligerent message included threats as well to resume long-range missile tests and to begin reprocessing spent fuel rods from its nuclear reactor to make atomic bombs.
The isolated Stalinist regime withdrew from the 1968 Nuclear Nonproliferation Treaty as of Saturday and intensified its defiance with a huge rally in the capital, where a million people stood shoulder to shoulder in a downtown square embellished with anti-American banners and huge portraits of leader Kim Jong Il.
The North's harsh language appeared to grow in lockstep with international condemnation of its declaration Friday that it would no longer abide by the pact that served as the keystone in the global attempt to stop the spread of nuclear weapons.
In New Mexico, Richardson -- a former U.N. ambassador -- said North Korea's deputy U.N. Ambassador Han Song Ryol assured him the North wanted improved ties with the United States and had no plans to build a bomb.
North Korea's U.N. Ambassador Pak Gil Yon told CNN on Saturday that Pyongyang "tried our best until the final moment" before Friday's declaration to resolve the dispute with the United States.
"As we consistently maintain, problems should be resolved through the negotiations, by peaceful means," Pak said. "The solution will be made through such a negotiation if the United States has a sincere attitude."
The threat of new missile tests came from the North's ambassador to China, Choe Jin Su, who said tests could resume if the United States does not take steps to improve relations.
"Because all agreements have been nullified by the United States' side, we believe we cannot go along with the self-imposed missile moratorium any longer," Choe said in Beijing.
New tests would be the first since 1998, when North Korea fired a missile over Japan into the Pacific. Pyongyang later imposed a moratorium on tests which was to last into 2004.
Another official left open the possibility of the North reprocessing spent fuel rods from its nuclear reactor to make atomic bombs. The United States believes North Korea already has one or two nuclear weapons and could make more in six months if reprocessing to extract plutonium is resumed.
Son Mun San, in charge of Pyongyang's relations with the U.N. International Atomic Energy Agency, said in Vienna, Austria, that spent fuel rods were locked down after a 1994 deal under which the Clinton administration promised big oil deliveries and two light-water nuclear reactors in return for North Korea shutting down its Yongbyon nuclear facility.
Spent fuel from that type of reactor is more easily converted to materials for nuclear bombs. Both sides have stepped back from the deal since the North allegedly told the United States in October it had a secret nuclear program.
Son said the reprocessing plant now stands in a state of "readiness." He said the reactor at the site would be up and running in a matter of weeks, roughly in line with earlier forecasts by the Vienna-based nuclear agency.
On Saturday, a newspaper commentary carried by the North's state news agency KCNA warned: "If any forces attempt to encroach upon the sovereignty and dignity of the DPRK, it will mercilessly wipe out the aggressors and mete out stern punishment to them."
DPRK stands for Democratic People's Republic of Korea, the country's official name.
Since the nuclear standoff resumed, the North has removed seals placed on the Yongbyon facility by IAEA monitors and expelled two inspectors as part of its renunciation of the 1994 U.S. deal.
Now, since the North dropped out of the nonproliferation treaty effective Saturday, the world community has grounds to take the issue to the U.N. Security Council, which could impose economic and political sanctions could on Pyongyang.
The North has said it would consider sanctions "a declaration of war."
Russia said Saturday it was too soon for council action and urged a diplomatic solution that included a package of humanitarian and economic programs for the Korean peninsula. Nuclear energy minister Alexander Rumyantsev suggested Moscow build a nuclear power station in North Korea to help with the impoverished North's energy program and bring it back in line with the 1994 agreement.
In the South Korean capital of Seoul, about 30,000 people rallied in support of the U.S. military presence as a deterrent to an attack from the North.
But the tone in Pyongyang was vitriolic. Premier Hong Song Nam said North Korea was determined to "defend its right to exist from the U.S. imperialists who put an 'axis of evil' cap on us and forced its lackey International Atomic Energy Agency to adopt a resolution to defame the Republic."
Another official called for launching "a holy war against the United States with a military-led might," as the crowd shouted in unison in response.
Still another urged that the North "punish the enemy with bloody revenge that we have harbored for 100 years."
Other squares, plazas and streets of Pyongyang also thronged with people "with burning hatred for the U.S. imperialists," the official news agency said.
The main square held posters with anti-American slogans, such as a large drawing of a North Korean soldier killing U.S. troops with a bayonet. It said: "Whoever messes with us will not avoid death!"
Other banners called for an "iron hammer blow on U.S. imperialist devils" and "smash U.S. nuclear maniacs." The rallies ended with music from military brass bands.