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North Korea (search) began nagging its communist allies as early as the 1960s to obtain a nuclear reactor with the intent of launching a hidden weapons program, according to former Soviet bloc documents released Tuesday.

Over the next two decades, responses generally were negative, sometimes to the point of hostility.

Having largely failed during the Cold War (search), North Korea in the years since then as put together a nuclear program that the Bush administration considers the equal of Iran's as a potential problem for the United States.

Just this week, the United States said a North Korean nuclear test, which some U.S. analysts say may be a prospect, would be considered an act of defiance and would be punished.

The newly released documents, mined from the archives of the Russian Foreign Ministry (search) and the Hungarian government, lay out a sequence of appeals, rejections and threats involving the North Koreans.

A memorandum from the Hungarian Foreign Ministry dated Feb. 16, 1976, quoted O Song Gwon, a third secretary of the North Korean Embassy in Budapest, and Yi Un gi, that embassy's deputy military attache.

"In their opinion," the memo said, "Korea cannot be unified in a peaceful way. They are prepared for war. If a war comes in Korea, it will be waged by nuclear weapons, rather than by conventional ones."

Then, it goes on: "By now the DPRK also has nuclear warheads and carrier missiles, which are targeted on the big cities of South Korea and Japan, such as Seoul, Tokyo and Nagasaki, as well as on the local military bases, such as Okinawa."

The official name of North Korea is the Democratic People's Republic of Korea (search).

The memorandum, signed by Istvan Garajszki, goes on to say: "When I asked whether the Korean People's Army had received the nuclear warheads from China, they replied that they had developed them unaided through experimentation, and they manufactured them by themselves."

"It was an idle boast. It's just curious," Kathryn Weathersby, senior associate at the Wilson International Center for Scholars, said Monday. "My reading of it is first of all, it shows how eager they were to be able to claim that. That claim was untrue, but they wanted it to be true."

In the early 1960s, most of the world was trying to rebottle the nuclear genie released over Japan to end World War II. The United States and the Soviet Union established a teletype "hot line" between Washington and Moscow in 1963 to prevent accidental nuclear war. That same year, the first test-ban treaty was signed to outlaw nuclear weapons testing in the atmosphere, outer space and underwater. The signature Nuclear Non-Proliferation Treaty was agreed in 1968.

However, in 1963, the North Koreans not only suggested that the Russians give them nuclear missiles, but also sought the green light to obtain nuclear weapons technology abroad, according to documents citing conversations the Soviet ambassador to North Korea, Vasily Moskovsky, had with his fellow ambassadors from Czechoslovakia and East Germany regarding their dealings with the North Koreans.

Through it all, the North Koreans kept petitioning their allies for nuclear reactors.

Hungarian Ambassador Ferenc Szabo filed a report from Pyongyang, North Korea's capital, to the foreign ministry in Budapest in 1979 that gave a rundown on capitalist South Korea's nuclear successes.

It said North Korea had been urging Czechoslovakia, the Soviet Union, Yugoslavia, China and others for years "to provide it with equipment for nuclear power plants or even to build a nuclear power plant.

"She tries to make up for her lag behind South Korea in this way, with the hidden intention that later she may become capable of producing an atomic bomb," Szabo said.

The documents are being released by the Korea Initiative of the Washington-based Woodrow Wilson Center's Cold War International History Project.