TOKYO (Reuters) - North Korea threatened to stop taking apart its nuclear plant that makes bomb-grade plutonium unless Japan provides it with energy aid as part of an international disarmament deal, Kyodo news agency said on Monday.

The threat is the latest snag in the sputtering deal the North struck with five regional powers and comes about two weeks after the United States called for a halt in all energy aid to punish Pyongyang for failing to agree this month to a system to check claims it made about its atomic programs.

Kyodo quoted a Beijing-based diplomat who participates in the six-way nuclear talks as saying: “Unless Japan implements the heavy fuel assistance, the (disablement) activities will be suspended.”

Kyodo later said Yoshihiro Kawakami, a Japanese lawmaker from the opposition Democratic Party, had quoted the diplomat as making the remarks in a meeting in the Chinese capital.

Japan has said it would not provide fuel aid unless the North settles problems caused by its agents abducting Japanese citizens decades ago and holding them in the reclusive communist state.

North Korea has received about half of the 1 million metric tons of heavy fuel oil, or aid of equal value, as a part of the deal it struck with China, Japan, Russia, South Korea and the United States for previous progress it has made on ending its nuclear arms program.

Energy-starved and destitute North Korea relies heavily on fuel aid to keep its few factories running.

The Beijing-based diplomat also said that 90 percent of the disablement work at the Yongbyon nuclear complex, which is capable of making weapons-grade plutonium, has been completed under the terms of last year’s denuclearization-for-aid deal, Kyodo reported.

Kawakami, an executive of a Japanese non-partisan group of lawmakers seeking to promote normalization of Tokyo’s ties with Pyongyang, had quoted the diplomat as saying the remaining 10 percent depended on Japan’s willingness to fulfill its obligations under the multilateral deal, Kyodo said.

South Korea has also called on Japan to contribute fuel aid, saying each country in the talks has bilateral problems with North Korea but ending Pyongyang’s atomic ambitions is a much greater concern than the grievances of any one country.

Most of the steps to disable the North’s Soviet-era Yongbyon nuclear plant have been completed. The steps are designed in total to take a year to reverse.

A think-tank affiliated with South Korea’s Foreign Ministry said separately the North may want to test U.S. President-elect Barack Obama’s team after it takes office in January.

“We cannot rule out a possibility that North Korea may threaten to suspend its denuclearization process, boycott the six-party talks and fire missiles or a test nuclear weapon ... so as to tame the new Obama administration,” Yonhap news agency quoted the report from the Institute of Foreign Affairs and National Security as saying.