Picture exclusive by Brennan Simpson

Britain’s Eurovision hopeful Antony Costa unfastens his trousers then casually urinates against a cash machine.

The singer – whose group Blue were chosen to represent the country in the song contest just three days earlier – is ­pictured near Trafalgar Square, only 30 yards from a ­public toilet.

The 29-year-old father of one relieves himself while deep in conversation on his mobile phone, leaving a pool of urine on the ­pavement.

After finishing the call, he ­reaches into his back pocket for his ­wallet.

He eventually re-fastens his ­trousers – with total indifference to other people needing to use the Post Office cash machine – after withdrawing a wad of notes.

BBC bosses, who screen ­family favourite Eurovision to a Saturday evening audience of ­millions, have hailed Costa and Blue as the ­“perfect choice” to represent the UK in this year’s contest.

As part of its coverage, the ­Corporation is screening a prime-time, one-hour documentary about the group for whom Eurovision offers a lucrative opportunity to return to the ­public eye.

But Costa’s ­shameful behaviour – symptomatic of the worst excesses of anti-social, binge-drinking Britain – may now force a BBC re-think.

The Sunday Mirror has passed on the photographs to the ­Metropolitan Police, who will be ­confronting Costa. He could face a fixed-­penalty fine of up to £100.

Police have launched a crack-down on yobs who urinate and vomit in the street in response to public outrage at behaviour which nightly shames towns across ­Britain.

They will be particularly ­irritated that he didn’t use a public lavatory which was in such easy reach.

Costa, whose hits with Blue ­include Sorry Seems To Be The Hardest Word and All Rise, relieved himself almost within view of Charing Cross police station.

George Iatrou, manager of the Post Office on William IV Street where the incident took place, said Costa should be dropped from Eurovision.

“This is appalling,” he said. “We clean the machines every day but what he has done is disgusting. We shouldn’t have to clean up after people behaving like this – it’s not a civilised way to ­behave.”

The Sunday Mirror revealed last week that Blue – who formed in 2001 and have sold 13 million records – will be the UK’s Eurovision choice.

The contest is expected to be watched by seven million viewers here and 70 million across Europe when it is staged in Dusseldorf on May 14.