Chris Holmes, from Sawston in Cambridgeshire, told airport bosses he wanted to devote "time and energy" to his family and business interests.

An image of the iced resignation went viral on Twitter within hours of Mr Holmes' brother-in-law posting it on the social networking site.

The Border Force said Mr Holmes "leaves with our best wishes".

Mr Holmes delivered the white iced resignation cake on Monday, his 31st birthday. He had worked at the airport as an immigration officer for four years.

He tweeted he was "overwhelmed by the positive response" from members of the public.