Japan's Prime Minister Shinzo Abe speaks during a news conference at his official residence in Tokyo in this March 15, 2013 file photo. [Photo/Agencies]

The hawkish Abe, who cemented his grip on power in an upper house election last week, called on Friday for an unconditional meeting between Japanese and Chinese leaders.

Often fragile Sino-Japanese ties have been seriously strained since September, when a territorial row over tiny islands in the East China Sea flared following Japan's nationalisation of the uninhabited isles.

Concern that the conservative Japanese leader wants to recast Japan's wartime history with a less apologetic tone has added to the tension.

"Vice Minister Saiki will visit China on July 29-30 and exchange views with Chinese officials," a Japanese foreign ministry spokesman said. He did not give further details.

China's Foreign Ministry responded to Abe's overture on Friday by saying its door was always open for talks but that the problem lay in Japan's attitude.

"The crux of the matter at present is Japan's unwillingness to face up to the serious problems which exist in Sino-Japan relations and it is avoiding having earnest talks and consultations with China," the ministry said in a statement faxed to Reuters. Japan, it said, should "stop using empty slogans about so-called dialogue to gloss over disagreements".