A senior Republican with links to Donald Trump has claimed “the jury is out” on whether Barack Obama ordered the tapping of the property tycoon's phone line during last year’s election.

Randy Neugebauer, a former Congressman who held talks with Mr Trump in January, said the President “thinks, or has the information, that leads him to believe that that did occur”.

The comments suggest leading Republicans may be willing to back the President's claims, which have so far come in a series of tweets without any substantiation.

Obama spokesman responds to Trump's wiretapping accusations

“How low has President Obama gone to tapp [sic] my phones during the very sacred election process,” Mr Trump wrote on Saturday morning. “This is Nixon/Watergate. Bad (or sick) guy!”

However, he failed to provide any evidence of the claims, which Mr Obama denied a short while later.

Mr Neugebauer is tipped as favourite to head the Consumer Finance Protection Bureau – an agency he has also vowed to dismantle - and held talks with Mr Trump in the then-President Elect’s New York tower shortly before his inauguration.

Asked about the claims during a visit to London Metropolitan University, the former Texan Congressman said: “The jury is out on that.

“I think the President thinks he has enough information that he can show some kind of operation was carried out.

“The question is what prompted that law agency to do that.”

Mr Neugebauer, who was named as one of the six most conservative members of the US House of Representatives, added: “We have a process in this country for initiating a wiretap and the process is designed to ensure you have proper cause.

Despite the severity of his claim Mr Trump has not provided any evidence Mr Obama was responsible for surveillance at his property (Reuters)

“For whatever reason President Trump thinks, or has the information that leads him to believe, that that did occur.”

His intervention came as Trump aides Kellyanne Conway and Sarah Huckabee Sanders said the President firmly believed the allegations he made on Twitter.

But Mr Obama's director of national intelligence, James Clapper, said nothing matching Mr Trump's claims had taken place.

"Absolutely, I can deny it," said Mr Clapper, who left government when Mr Trump took office.

The House and Senate intelligence committees and the FBI are investigating contacts between Mr Trump's campaign and Russian officials, as well as whether Moscow tried to influence the 2016 election.

On Sunday, Mr Trump demanded that they broaden the scope of their inquiries to include Mr Obama's potential abuse of his executive powers.