The ultra-light banners were attached to the flies with natural wax and after a short time the banner dropped off by itself. A spokesperson for the agency said that no fly was harmed.

A brilliant a piece of buzz marketing.

Following a successful tour of other UK cities, the Eden channel has donated the sculpture to the Royal Zoological Society of Scotland who are the owners of Mercedes, the only polar bear in the UK.

Melting ice caps threaten the existence of polar bears as their habitat disappears. There will also be serious consequences for the two billion people who depend on glacial meltwater to feed rivers.

A total of 15 artists spent two months constructing the 20ft by 20ft square structure, which travelled up the Thames, stopping beside Tower Bridge and the Houses of Parliament. The bear was also promoting the launch of a new digital TV channel devoted to natural history.

Adrian Wills, head of the Eden channel (Sky 532 and Virgin Media 208), hoped it would address issues like climate change in an informative and entertaining way: “The Earth is a fragile place and we were keen to launch with a message that would draw attention to the uncertain state of our finely balanced environment.”

The PR campaign has won prizes at 4 major awards ceremonies in the last month including the PR Week Awards, Brand Experience Awards, the PRO awards and the Event Awards.