To be or not to be: Window cleaner who believes his family owns the only portrait of William Shakespeare made in his lifetime battles to prove £200m painting is the real deal after academics raised doubts

To be or not to be: in the case of this portrait, that really is the question. For a window cleaner believes his family could own the only picture of William Shakespeare painted during his lifetime.

And, if authenticated, it could be worth up to £200million.

Steven Wadlow, 58, said his father bought the painting from the Great Tew Estate in Oxfordshire in the 1960s and hung it, largely unnoticed, in the living room for decades.

But in 2012 his father, Peter, watched a documentary about the playwright in which he couldn't help but remark: 'He looks like our bloke above the telly.' After he said this to his son, Mr Wadlow began trying to validate the painting, with X-rays dating it to 1595 when the Bard would have been about 31.

Steven Wadlow, 58, pictured with the painting he believes to be of William Shakespeare

Mr Wadlow said his father bought the painting from the Great Tew Estate (pictured) in Oxfordshire in the 1960s

The portrait dubbed by experts as The Wadlow Portrait may be in fact a life time portrait of William Shakespeare

The Droeshout portrait of William Shakespeare circa 1623. Several other portraits from the 17th century allegedly show the playwright during his lifetime

Experts have since determined it is from the right period, is not a copy and could be the only authenticated portrait of Shakespeare from his lifetime.

But Mr Wadlow, from Aylesbury in Buckinghamshire, said many academics have not taken him seriously.

He told The Sun: 'Because I'm a working-class tradesperson, the people who have been studying this for years, they don't want to find this out from a no-one.' There are only two unambiguous portraits of Shakespeare, both of which were painted after his death in 1616.

Several other portraits from the 17th century allegedly show the playwright during his lifetime, although in all of them the sitter is either unidentified or the resemblance has since been subject to debate. Mr Wadlow accepts he may never know the truth about the portrait, which he keeps in safe storage, but said: 'Let's get it out and talk about it.'