BEIJING (REUTERS) - China's state media have published for the first time the photograph and resume of Premier Li Keqiang's wife, a professor of English who has translated several books on American literature.

State news agency Xinhua said on Sunday that Mr Li was married to Madam Cheng Hong, who is aged 56 or 57. The couple, who left on Sunday for an official tour of Africa, have one daughter and met at the elite Peking University, Xinhua said.

The move to put Mdm Cheng on public display could reflect a new effort by China to cultivate soft power and burnish its image on the international stage.

Mdm Cheng has taught in the foreign languages department of the Capital University of Economics and Business for more than 30 years, Xinhua said. She specialised in English teaching and research and was responsible for a research project on "natural literature and eco-criticism".

Mdm Cheng's unveiling is unusual, as Chinese leaders generally keep secret the details of their personal lives.

The wife of former Premier Wen Jiabao never travelled with him, though the wives of former premiers Li Peng and Zhu Rongji accompanied them on trips, the Beijing News reported on Monday, citing a former foreign ministry official.

Chinese President Xi Jinping's wife, Peng Liyuan, has decisively broken the mold of Chinese first wives, who have kept an intentionally low profile since the 1970s.

Mdm Peng, a famous singer, has been photographed playing steel drums in Trinidad, strolling hand-in-hand with a coffee farmer's daughter in Costa Rica and snapping pictures with her iPhone in the shadow of Mayan ruins in Mexico.

Chinese leaders' wives have usually kept a low profile because of the experience of Jiang Qing, the widow of the founder of Communist China, Mao Zedong.

Mdm Jiang was the leader of the "Gang of Four" that wielded supreme power during the 1966-76 Cultural Revolution. She was given a suspended death sentence in 1981 for the deaths of tens of thousands during that period of chaos.