Mr Johnson then turned to a Chinese student, asking: “The yin and the yang. What do you say for a harmonious, sounds like one of those Chinese fireworks, a harmonious dove or something like that? A pair of harmonious doves. What is that in Chinese?”

After she looked back blankly, Mr Osborne said: “I think she likes the yin and yang comparatively.”

Earlier, the mayor could not resist a friendly dig at Mr Osborne, who in a speech at the university mentioned that his 10-year-old daughter was learning Mandarin.

Mr Johnson then told the same audience that not only was his daughter learning the language but also planned to visit China next week.

Mr Johnson said: “George mentions his daughter, I have a 16-year-old and she is not only learning Mandarin George, she’s coming here next week to pursue her studies.”

After the speeches, Mr Johnson proved more popular in a question and answer session, with just one question directed at Mr Osborne.

The mayor and the Chancellor have long been touted as successors to David Cameron as Conservative Party leader and their visits come at a time of thawing relations following a diplomatic row over the Prime Minister meeting the Dalai Lama last year.

Both Mr Osborne’s and Mr Johnson’s trips have been in the pipeline for months but the timing of the Chancellor’s visit was revealed more recently than the mayor’s.

Yesterday, Mr Johnson stressed he was “very pleased” that Mr Osborne was visiting while admitting the timing was handled by the Government.

Sources: ITN/PA