A U.S. official says North Korea is blocking progress in six-party talks aimed at resolving the impasse over its nuclear program.

Christopher Hill, Assistant Secretary of State for East Asia and Pacific Affairs, and key negotiator in the six-party talks says the ball is in North Korea's court when it comes to any resumption of the talks with United States, China, Russia, South Korea, and Japan.

North Korea said this week it will not return to the talks and blamed U.S. pressure over Pyongyang's counterfeiting and money laundering activities, key issues on a longer U.S list of concerns.

Assistant Secretary Hill told the House Asia-Pacific Subcommittee Pyongyang is responsible for the current pause. "Five of the six countries are ready to come to Beijing, and ready to sit down as soon as these talks are scheduled. Five countries are already ready and I have my bags packed for that and the problem has been that the North Koreans are not yet ready to come. When they do they will find us ready to press ahead with the implementation of all of the elements of this September agreement," he said.

North Korea has long denied allegations by the United States and others that it uses illicit financial activities to support its military and weapons development programs.

Republican Congressman Jim Leach is concerned about the impact the latest delay in the six-party talks could have on efforts to resolve the North Korean impasse. "At the same time that the malfeasance of the North Korean government has brought us to this impasse, it remains in the interest of the United States to initiate additional dialogue even if prospects for its success are uncertain," he said.

Congressman Leach cautions the Bush administration against what he calls a "reactive" approach in dealing with Pyongyang, saying this could strengthen hard-line elements in Pyongyang, while giving others the impression that Washington is blocking progress.

One Democrat lawmaker who is a key critic of Beijing expressed skepticism about the level of China's cooperation in pressuring Pyongyang to end its pursuit of nuclear weapons. "When it comes to stopping North Korea's nuclear program, China cooperates sufficiently with us to get good words out of our State Department, but not sufficiently with us to actually stop North Korea from building their nuclear weapons," said Congressman Brad Sherman.

Before Wednesday's hearing was shortened by legislative votes in the House, some lawmakers expressed concern about other issues involving China and its relations with the United States.

On Taiwan, Ohio Republican Steve Chabot, a member of the congressional Taiwan Caucus, blames Beijing for what he calls provocations that have worked to keep tensions high with Taipei. "In my view, the provocation has been on the other side, from the P.R.C., such things as continuing to increase the number of missiles that are facing Taiwan across the Taiwan Straits. To me that would be provocation, as well as passing the anti-secession law some time ago after being warned that that would be an act of provocation they nonetheless went ahead with that," he said.

China accused Taiwan this week of what Beijing called deliberate provocations and obstructions in the wake of a statement by Taiwan's President Chen Shui-bian that a National Unification Council had "ceased to function."

Beijing criticized the United States saying Washington had downplayed the move sending what it called "false signals" to Taiwan.

Assistant Secretary Hill Wednesday repeated the longstanding U.S. "One China" policy, adding Washington continues to caution against unilateral moves by Beijing or Taiwan and urge that issues be resolved through dialogue.

He also looked ahead to Chinese President Hu Jintao's upcoming visit to the U.S. "We expect that President Hu will want to build on what we hope will be a successful joint commission on commerce and trade that deals with intellectual property rights, market opening, and China's commitment to Doha [free trade] development goals, among other issues. And we also expect to engage President Hu on a range of human rights and religious freedom topics," he said.

The Chinese president is scheduled to visit Washington next month and U.S. officials have said Beijing's monetary policies, among other issues, will be near the top of the bilateral agenda.