The State Department said Monday that what North Korea has shut down under a six-party deal cut in February is a 5-megawatt nuclear reactor in Yongbyon, one of the five facilities that Pyongyang agreed to close with a U.N. nuclear watchdog.

The department issued the statement in response to a media inquiry about which of the five nuclear facilities the IAEA confirmed North Korea has shut down.

"The International Atomic Energy Agency has verified that North Korea has shut down the 5-megawatt reactor at the Yongbyon complex, and intends to verify the status of the remaining four facilities by Wednesday, July 18," the department said in a statement.

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The five consist of the four facilities in Yongbyon — the 5-megawatt nuclear reactor, a spent fuel reprocessing facility, a 50-megawatt reactor under construction and a fuel fabrication plant — as well as a 200-megawatt reactor under construction in Taechon.

Washington used the plural form of "nuclear facilities in Yongbyon" when referring to what was closed, but Pyongyang used the singular form of "the Yongbyon nuclear facility" in announcing the closure.

Under the Feb. 13 six-way agreement, North Korea was to shut down and seal its nuclear facilities in Yongbyon and invite IAEA inspectors back into the country by April 14 in exchange for the start of the shipment of 50,000 tons of heavy fuel oil.

While that deadline was not met due to a banking row, a solution to the dispute late last month prompted North Korea to say last week that it was considering starting the shutdown of the facilities at Yongbyon after receiving roughly one-tenth of the oil.

South Korea sent the first shipment of fuel oil totaling 6,200 tons — more than one-tenth of the 50,000 tons — as an initial measure Thursday, and it reached North Korea early Saturday.

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