SEOUL (Reuters) - North Korea said on Sunday the United States had rejected an invitation to send one of its top diplomats to Pyongyang, accusing Washington of trying to shift the blame for the deadlock in denuclearisation talks on the North.

Sung Kim has been meeting with officials of the countries that had been part of the so-called six-party talks in the past week in Tokyo and Beijing, where he said it was up to the North to show it was serious about ending its nuclear programme.

"(We) invited Kim Sung to visit Pyongyang as he expressed his willingness to meet with his counterpart of the (North) during his visit to Asia this time," the North's KCNA news agency quoted an unnamed foreign ministry spokesman as saying.

"However, the U.S., in disregard of this, is working hard to shift the blame onto the (North), misleading public opinion by creating impression that dialogue and contacts are not realized due to the latter's insincere attitude."

Kim said in Beijing on Friday that Washington was "open to engagement, substantive dialogue with North Korea about the issue of denuclearisation".

He did not mention a possible trip to Pyongyang or an invitation by North Korea to visit for talks. The U.S. embassy in Seoul did not immediately have comment.

In Washington, the State Department denied the United States and North Korea had planned for a meeting.

In 2005, North Korea reached an agreement with the United States, South Korea, China, Japan and Russia to suspend its nuclear programme in return for diplomatic rewards and energy assistance.

Negotiations collapsed after the last round of talks in 2008. North Korea declared the agreement void after refusing inspections to verify compliance with the deal.

North Korea has called for the resumption of the talks, but the United States and South Korea have said Pyongyang must first show it was serious about ending its nuclear programme.

Pyongyang has said it was willing to suspend nuclear testing if the United States halted annual joint military drills with South Korea. Washington and Seoul rejected the proposal saying the drills were for defensive purposes.

(Reporting by Jack Kim and Kahyun Yang; Editing by Jeremy Laurence)