A Japanese daily says China's Communist Party strongly protested the nuclear test North Korea conducted in May last year.

The Asahi Shimbun said Tuesday that China also urged the North to open up, dismantle its nuclear program and abandon the father-to-son power transition course it is currently on.

The paper said it is highly unusual for Beijing to make demands that border on interference in domestic affairs in Pyongyang, with which China maintains favorable ties.

Asahi said the North's open-door and reform policies and moves to return to the six-party nuclear talks appear to be due to Chinese pressure.

But the Chinese Foreign Ministry denied the Asahi report.