China is stepping up efforts to persuade North Korea to return to the six-party talks aimed at resolving its nuclear crisis.

Sources in Beijing said Wang Jiarui, head of the Chinese Communist Party's international liaison department, would visit North Korea from February 19 to 22 as part of efforts to resolve the North's nuclear issue.

Wang's impending visit comes in the wake of North Korea's surprising declaration last Thursday that it possessed atomic weapons and was pulling out of stalled six-way nuclear talks.

However, the Chinese official's visit has raised doubts over how sincerely the North Koreans and Chinese will discuss related matters, as it was planned as a part of regular bilateral exchanges between Pyongyang and Beijing and the agenda reportedly does not include key pending issues.