Theresa May has 'failed in her objective' unless exit poll is 'incredibly wrong' says election guru John Curtice

The Conservatives may still have a majority however, he said

Britain's Prime Minister Theresa May arrives to vote in the general election at polling station in Maidenhead, England (AP)

Theresa May has "failed in her objective" of getting a big majority for the Conservative party unless the exit poll is "incredibly wrong", the UK's top political scientist has said.

John Curtice, Professor of Politics at the University of Strathclyde, said it was also likely that Labour would not be the largest party, however.

The psephologist told the BBC: “It seems to me that unless the exit poll is incredibly wrong that the Prime Minister has failed to achieve her principle objective, that was she was going to achieve a landslide or at least a very big majority for her party in the next House of Commons and thereby provide her with potentially rather more wiggle room over Brexit.

“I think the second thing we can probably rule out is that the Labour party is going to end up with more seats than the Conservatives and that indeed we are still talking about Theresa May or at least somebody from the Conservative party heading the next administration.”

He added a warning about the accuracy of the exit poll: “We certainly cannot rule out the possibility that the Conservatives will still have an overall majority but maybe one that isn’t much bigger than when the election was called."

Professor Curtice is one of the key academics who runs the Sky/BBC/ITV exit poll, which shows the Conservatives possibly falling short of a majority.

One of the psephologist's colleagues, YouGov pollster Peter Kellner, however said that even a small error with the exit poll could result in a large Tory majority.

Sir David Butler, veteran political scientist and the inventor of the swing-o-meter, said: "Higher youth turnout in Sunderland may hint at explaining Labour strength generally".