US House Speaker Paul Ryan, the nation's top elected Republican, told politicians on a conference call he will no longer "defend" or campaign with Donald Trump. Picture: Mandel Ngan/AFP

He told his party on Monday that he now is focusing on ensuring Hillary Clinton doesn’t get a blank cheque as president with a Democratic-controlled Congress, suggesting that he doesn’t believe Trump can win the election.

The news comes as the latest NBC News/Wall Street Journal poll shows Clinton is now beating her Republican rival by double-digits.

House Speaker Paul Ryan refuses to defend Donald Trump. Picture: AP Photo/Cliff OwenSource:AP

PAUL RYAN REFUSES TO DEFEND TRUMP

Ryan’s office quickly said he was not conceding the election’s outcome. But pro-Trump GOP House members got that impression, pushing back and saying Trump can still win and should not be abandoned.

In a conference call with GOP politicians, Ryan said he wouldn’t defend Trump or appear with the Republican presidential candidate for the rest of the campaign. Several people on the call said Ryan explicitly told House members, “You all need to do what’s best for you in your district.”

The remarkable development came after yesterday’s bitter second presidential debate and as Trump battled to rescue his campaign after the release last week of a 2005 video in which he is heard bragging about how his fame allowed him to “do anything” to women.

Several leading Republicans have withdrawn their support or called for him to drop out of the race.

Ryan alongside Trump’s running mate Mike Pence. Picture: Chip Somodevilla/Getty Images/AFPSource:AFP

Ryan’s message appeared to signal his disbelief in Trump’s ability to turn the campaign around with four weeks until Election Day, though he didn’t actually revoke his endorsement.

He said his decision was driven by what he thought was best for the Republican-led Congress, not himself, according to people on the call.

Those politicians weren’t authorised to be quoted by name and demanded anonymity.

Ryan said he will “spend his entire energy making sure that Hillary Clinton does not get a blank cheque with a Democrat-controlled Congress,” one such person said. Ryan added that he was “willing to endure political pressure to help protect our majority.”

In the eyes of many Republican leaders, the recent released tape of a 2005 conversation in which Trump made vulgar, predatory comments about women not only jeopardised his own uphill candidacy, but that of Republicans fighting to hold their majority in the Senate. Their commanding majority in the House could now be in peril, too.

CLINTON TROUNCES TRUMP IN NEW POLL

As Trump’s campaign reels over his controversial “pussy” comments, the Republican nominee now trails his Democratic rival in the polls.

The new NBC News/Wall Street Journal poll, conducted on Saturday and Sunday before the second presidential debate, shows Clinton with 46 per cent support among likely voters in a four-way matchup, compared to 35 per cent for Trump.

Also included in the poll of 500 voters was Libertarian Gary Johnson and Green Party candidate Jill Stein.

Among all registered voters, Clinton’s lead is 13 points — her largest lead over Trump since the poll began testing the pair last September.

Hillary Clinton leads Donald Trump in a new poll. Picture: AFP/ Paul J. RichardsSource:AFP

WARREN BUFFETT LASHES TRUMP OVER TAX

Billionaire investor Warren Buffett has hit back at Trump, releasing his own tax information and challenging the New York developer to do likewise.

The claim followed Trump’s assertion in a televised debate on Sunday that, like himself, Buffett had avoided paying income taxes by deducting sizeable business losses.

Buffett, founder and head of the Berkshire Hathaway conglomerate, said this was untrue.

“He has not seen my income tax returns. But I am happy to give him the facts,” Buffett said in a statement.

Billionaire Warren Buffett ahs endorsed Hillary Clinton for president. Picture: AFP/Nicholas KammSource:AFP

Buffett, who has endorsed Clinton, said that for 2015 he had declared gross income of $US11.6 million and, after $US5.5 million in deductions for charitable contributions and state taxes, paid $US1.8 million in federal taxes.

Buffett noted that he gave charities nearly $US2.9 billion last year but only could deduct $US3.5 million of that. Trump however has not released his tax data.

Tax records published by The New York Times this month showed Trump had declared a $US916 million loss in 1995, allowing him to pay no federal income tax for up to 18 years.

During Sunday’s debate, Trump said he had indeed used the losses to avoid taxation. “Of course I do. Of course I do,” he said, adding that Buffett had done likewise. Buffett said that was incorrect.

“I have paid federal income tax every year since 1944, when I was 13. (Though, being a slow starter, I owed only $7 in tax that year),” he said. “I have copies of all 72 of my returns and none uses a carryforward.”