The Tory election campaign suffered its worst day after Boris Johnson was branded a “disgrace” for failing to look at a photograph of a sick four-year-old boy lying on a hospital floor for several hours awaiting medical treatment.

With less than three days to go to polling day, the Prime Minister was forced onto the back foot as political opponents seized on his misjudgement.

During an ITV interview, Mr Johnson finally looked at the picture of Jack Williment-Barr, lying on the floor of Leeds General Infirmary; an oxygen mask near his face.

He described it as a “terrible, terrible photo” and apologised; but the political damage had been done.

The Herald: Camley's Cartoon: PM branded a "'disgrace" over hospital photo.Camley's Cartoon: PM branded a "'disgrace" over hospital photo.

Jeremy Corbyn, brandishing a copy of Jack’s photo, told a rally in Bristol: “He's had nine years to properly fund the NHS. A child being treated on the floor is a disgrace to our society."

Today, with 48 hours of campaigning left, the Conservative leader will try to seize the initiative as one poll put the Tory lead at six points; hung parliament territory.

On a campaign visit to Staffordshire, the PM will say it is “time to send in the bulldozers” to smash through the parliamentary gridlock on Brexit.

He will warn of “sophisticated and well-financed attempts…to prevent a Conservative majority through tactical voting,” noting how opposition parties only needed 12 more seats to put the Labour leader in Downing St.

If this happened, Mr Johnson will warn, Britain would be stuck in “this first circle of hell for the foreseeable future” while the Conservatives only needed nine more seats for a majority, which would mean “we could finally get Brexit done, end the uncertainty and move on”.

Mr Corbyn is due in Scotland in the next 24 hours while Tory strategists are considering whether the PM will follow suit.