The United States is willing to show flexibility on its proposal for resolving a nuclear weapons impasse with North Korea if Pyongyang responds constructively when talks resume this month after a one-year delay, U.S. officials said. Pyongyang has faulted the June 2004 proposal for demanding that the reclusive communist state take significant steps, like disclosing all its nuclear programs, before Washington takes any action, according to Reuters. "It was a proposal, not a demand," one senior U.S. official travelling with Secretary of State Condoleezza Rice in Asia said en route to Phuket from Beijing on Sunday night. "It was to get things started, which is why it is important we hear back" from Pyongyang," said the official who briefed reporters on condition of anonymity. Rice, in Beijing before flying to Phuket to check on post-tsunami recovery efforts, said Washington and its partners in the six-party talks - China, South Korea, Japan and Russia - insist that North Korea be prepared to make progress when negotiations resume. --More 2234 Local Time 1934 GMT