(Reuters) - The foreign ministers of the United States, Japan and South Korea are expected to meet in Washington on Monday to discuss North Korea and other issues, U.S. officials said on Wednesday.
Washington is putting increasing pressure on China to rein in North Korea, but a foreign ministry spokesman in Beijing said what was needed was a revival of the stalled six-party talks involving the two Koreas, Russia, China, Japan and the United States.
Last week, North Korea fired a barrage of artillery rounds at Yeonpyeong island in the first such attack on civilians on South Korean soil since the end of the 1950-53 Korean war. Two civilians were among the four killed.
U.S. officials who spoke on condition of anonymity said Monday's meeting was expected to cover other regional security issues beyond North Korea and to include Secretary of State Hillary Clinton, Japanese Foreign Minister Seiji Maehara and South Korean Foreign Kim Sung-hwan.
Experts have voiced surprise at the sophistication of a uranium enrichment plant and light-water reactor at the North's main nuclear complex, which were shown to a U.S. scientist earlier this month. There has been no way to verify the North's claims.
The North is also seen as a proliferation risk, accused by the West of supplying Syria, and possibly Iran, with nuclear know-how.
"Currently, construction of a light-water reactor is in progress actively and a modern uranium enrichment plant equipped with several thousands of centrifuges, to secure the supply of fuels, is operating," the Rodong Sinmun newspaper reported.
"Nuclear energy development projects will become more active for peaceful purpose in the future," added the paper, according the state news agency KCNA.
The United States kept up pressure on China to use its influence with North Korea.
"The Chinese have a duty and an obligation to greatly impress upon the North Koreans that their belligerent behavior has to come to an end," White House spokesman Robert Gibbs said. "I think you'll see progress on multilateral discussions around this over the next few days."

Andrei Lankov, a North Korea expert at Seoul's Kookmin University, said Pyongyang was simply following a typical pattern.
North Korea has conducted two nuclear tests to date and is believed to have enough fissile material from its plutonium-based program to make between six and 12 bombs.
Kim Tae-young became the first political victim of the attack as China expressed muted criticism of forthcoming joint U.S-south Korean military exercises in the Yellow Sea.
President Lee Myung-bak accepting his minister's resignation "to improve the atmosphere in the military and to handle the series of incidents", a presidential official said.
North Korea fired a barrage of artillery shells at the island of Yeonpyeong off the peninsula's west coast on Tuesday, killing two civilians and two soldiers and destroying dozens of houses.

While China objected to the joint military exercises starting this weekend, North Korea threatened further attacks on the South if there were more "provocations".
Seoul said it would increase troops on islands near North Korea after the bombardment, which caused a sharp spike in tension in the world's fastest growing region.
"We have noted the relevant reports and express our concern about this," spokesman Hong Lei said, referring to the joint military exercises and the involvement of the nuclear-powered aircraft carrier the USS George Washington in the drill.

China has long propped up the Pyongyang leadership, worried that a collapse of the North could bring instability to its own borders. Beijing is also wary of a unified Korea that would be dominated by the United States, the key ally of the South.