North Korea 'very close' to restarting plutonium reactor

North Korea may be very close to restarting a plutonium reactor that can produce fissile material for nuclear bombs, a US research institute has said.

But the North's ability to put the 5-megawatt reactor back to work will depend on the availability of fresh fuel rods to power it, and that remains uncertain, reports The Japan Times.

The US-Korea Institute at Johns Hopkins School of Advanced International Studies is basing its conclusions on analysis of commercial satellite images, the latest taken May 22.

North Korea announced it plans to restart the reactor at Yongbyon in early April, amid a litany of threats toward the US and South Korea after it faced tougher international censure over its latest nuclear and rocket tests. The reactor was shuttered in 2007 under the terms of a disarmament agreement.

South Korean Defense Ministry spokesman Kim Min-seok said that the one-to-two month forecast for restarting the reactor was "a bit too early".

Threats by the North have subsided in recent weeks, and under pressure from ally China, Pyongyang has said it is willing to restart international negotiations but has not recommitted to a previous goal of abandoning atomic weapons.

State Department official Joel Wit, who is editor of the institute's website, 38 North, said North Korea's Weapons of Mass Destruction (WMD) program is moving ahead, adding that the purpose of restarting the 5-megawatt reactor is the production of more plutonium for more bombs.

An analysis being published by 38 North says a new system to provide cooling for the reactor appears almost finished, and two underground water tanks are now in place next to a building that would hold spent fuel.

North Korea is believed to have a supply of fuel rods, but many of them may need adapting for use in the reactor, making it uncertain whether the North is indeed in a position to restart the reactor. Analysts now put the North's arsenal at four to eight plutonium bombs.