Donald Trump's presidential campaign is on the brink after the Speaker of the House, Paul Ryan, became the latest name to say he will not campaign for him.

During a conference call with members of his party, the most senior Republican in the House of Representatives said he could no longer "defend" Mr Trump.

Mr Ryan, who as Speaker is the leading officer in the lower chamber of the US federal legislature, added that his priority was now to make sure that his party keeps control of Congress.

The Wisconsin Representative did not comment publicly but, according to one of those on the call, he said he would not campaign with or for the brash New York real estate mogul for the rest of the race.

The source said: "He will spend his entire energy making sure that Hillary Clinton does not get a blank cheque with a Democrat-controlled Congress."


Mr Ryan reportedly said to his colleagues: "You all need to do what's best for you in your district."

Two sources told Associated Press that Mr Ryan did not respond directly when asked: "Will you vote for Donald Trump?"

He later clarified that he was not removing his endorsement.

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Mr Ryan's words came after revelations of Mr Trump's lewd comments about women, sending the billionaire's campaign into damage control mode less than a month from the election.

In the 2005 recording, Mr Trump had boasted about his ability to grab women by the crotch with impunity, adding that, as a celebrity, "you can do anything".

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Following that and Sunday's debate with his Democratic Party rival Mrs Clinton, the latest national polls showed him trailing by around 4%.

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An angry Mr Trump hit back on Twitter, writing: "Paul Ryan should spend more time on balancing the budget, jobs and illegal immigration and not waste his time on fighting the Republican nominee."

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Some Republicans on the conference call criticised Mr Ryan and others for being too negative about Mr Trump, with California Republican Dana Rohrabacher reportedly calling the party's leaders "cowards", imploring them to leave their defeatist attitude behind.

Paul Ryan should spend more time on balancing the budget, jobs and illegal immigration and not waste his time on fighting Republican nominee — Donald J. Trump (@realDonaldTrump) October 10, 2016

Mr Ryan's spokesman AshLee Strong did not comment on the conference call, only saying that there was "no update in (Mr Ryan's) position at this time".

The top Republican in the Senate, Mitch McConnell, said on Monday that "I don't have any observations to make" about the presidential election.

Sky's US Correspondent Amanda Walker said: "After the latest most damaging scandal, Republicans willing to publicly support (Mr Trump) have been dropping like flies.

"Defending Donald Trump is a very tough gig at the moment."