North Korea added the 5-megawatt, graphite-moderated reactor to its nuclear complex in 1986 after seven years of construction.

But a graphite-moderated reactor would never be compact enough for submarines.

The light-water, graphite-moderated reactors were of similar design as those at Chernobyl.

Russian and British plutonium production also used graphite-moderated reactors.

It may mean that they will not build any more graphite-moderated reactors, as they had planned to."

The disablement must also include the North's graphite-moderated reactors and its post-treatment plants.

Since then, the agency has been limited to monitoring North Korea's graphite-moderated reactor as part of the 1994 agreed framework.

The power station had four water-cooled, graphite-moderated reactors.

Peach Bottom Unit 1 was an experimental helium-cooled, graphite-moderated reactor.

The North Koreans were using a small, twenty-five-megawatt thermal graphite-moderated reactor for this purpose.

Infamous examples include the accidents at Windscale and Chernobyl-both graphite-moderated reactors.

The modern light-water reactors produce far less plutonium than the graphite-moderated reactors used in North Korea.

- Syria was building a gas-cooled, graphite-moderated reactor that was nearing operational capability in August 2007.

Such reactors are considered "more proliferation-resistant than North Korea's graphite-moderated reactors", but not "proliferation proof".

A five-megawatt graphite-moderated reactor at Yongbyon has produced arms-grade plutonium that officials and experts believe the North used to build several nuclear bombs.

Unit 4 at Chernobyl was a water-cooled and graphite-moderated reactor -- a combination that can and did yield a runaway chain reaction.

In their communique, the two countries said it would be desirable for North Korea to replace its graphite-moderated reactors, with light-water-moderated reactors.

Heavy water reactors and graphite-moderated reactors can even use natural uranium as these moderators have much lower neutron capture cross sections than light water.

In 2013, North Korea restarted its 5 MW(e), graphite-moderated reactor located within the Yongbyon research complex.

The N Reactor on the Hanford nuclear reservation is similar in design to the light-water-cooled, graphite-moderated reactor at Chernobyl.

At that time, an American-led consortium agreed to replace North Korea's graphite-moderated reactors, which produce plutonium, with two light-water reactors.

Swedes visiting Moscow this week were reportedly told that plans for seven graphite-moderated reactors had been scrapped, including the fifth and sixth reactors for Chernobyl.

In return, the United States agreed to replace North Korea's graphite-moderated reactors with two light-water reactors, which are less useful in making bomb-grade material.

He said the construction of the Kursk, Smolensk and Ignalina stations, which use graphite-moderated reactors like the ones at Chernobyl, would be completed, with new safety elements.

It would also be linked to fulfillment of Mr. Kim's oft-stated goal to replace North Korea's old graphite-moderated reactors with newer light-water reactors.