Mayor Ken Livingstone is visiting China to promote London to businesses, tourists and students.
The mayor will open offices in two cities
During the week-long trip he will sign partnership agreements with his counterparts in Beijing and Shanghai and open offices in both cities.
Lord Coe, who led Britain's 2012 Olympic Games bid, is among 70 delegates travelling with the mayor.
They will also meet organisers of the 2008 Beijing Olympics to foster relations with the 2012 committee.
Mr Livingstone said: "China is one of the fastest-growing economies in the world, whilst London is a world-class centre of financial and business services.
"A stronger relationship between China and London will therefore be mutually beneficial; we both have much to gain from building closer links with each other."
Lord Coe said: "Beijing is four years ahead in hosting the Games and we have much in common in our aspirations to inspire change as well as creating a sporting legacy for our respective cities."