North Korea has a second uranium enrichment facility in operation on the country\'s west coast, in addition to its known facility at the main Yongbyon nuclear complex, a lawmaker claimed Wednesday. The underground facility in Dongchang county has been in operation since it was built between 2001 and 2006, Rep. Park Sun-young of the minor Liberty Forward Party said, citing a North Korean military official she claimed was in charge of security at the construction site. \"North Korea has already been developing nuclear weapons using enriched uranium since 2007, switching from its plutonium production program. But the (South Korean) government has not been aware of this fact,\" Park said in a release submitted at a parliamentary interpellation session. Uranium, when highly enriched, can become weapons grade, which would provide the North Korean regime with a second way of building atomic bombs in addition to using plutonium. Park claimed it was after the new plant began operation that the North invited New Mexico Governor Bill Richardson to Pyongyang last year and expressed its willingness to put the Yongbyon complex under international monitoring. North Korea expelled IAEA monitors in early 2009 after the U.N. Security Council condemned a rocket launch it made that was considered a long-range missile test. \"The Yongbyon facility has been almost emptied in preparation for international monitoring,\" Park said. \"South Korea and the U.S. have continuously been fooled by North Korea.\" Officials said it is difficult to verify Park\'s claims. The claims came amid a flurry of diplomacy to resume six-party talks, aimed at persuading North Korea to give up its nuclear weapons programs. The talks have been dormant since the last session in late 2008.