British Prime Minister Theresa May has apologised to the Conservative Party for her performance in the botched campaign for this year's snap election.

She admitted the campaign was "too scripted, too presidential" and said she took responsibility for its shortcomings.

After calling an election three years early in the hope of increasing her dominance in the House of Commons, Mrs May lost 13 MPs and forfeited her majority, forcing her into a deal with the Democratic Unionist Party.

She won long applause from party delegates as she said: "We did not get the victory we wanted because our national campaign fell short. It was too scripted. Too presidential.

"And it allowed the Labour Party to paint us as the voice of continuity when the public wanted to hear a message of change.

"I hold my hands up for that. I take responsibility. I led the campaign. And I am sorry."

Mrs May struggled to deliver her keynote speech to the Tory party's annual conference, repeatedly coughing and losing her voice.

With the party members applauding to keep Mrs May going, she had to stop on several occasions to drink water and take a cough sweet which she said came from Chancellor Philip Hammond.

"Shows what good the chancellor's cough sweet is," she said, as she continued to attempt to give her speech.

Earlier in the speech she was heckled by a protester who held up a P45 paper in front of her, a document handed out to employees leaving a job.

After a four-day conference dominated by speculation over Boris Johnson's leadership ambitions, Mrs May made no mention of her Foreign Secretary by name, instead praising the "team" around her in the Cabinet.

And she singled out for praise the Scottish Tory leader Ruth Davidson, often tipped as one of Mr Johnson's main potential rivals for the top post.

She repeatedly assured delegates that following the botched poll "we have listened and we have learned".

Mrs May also said she understands that some are finding the Brexit talks frustrating but that she is confident of getting a deal that will work for both Britain and the European Union.

She told party members that the British government was planning for every eventuality in the Brexit talks and said EU citizens living in Britain were welcome.