US President Donald Trump has asserted without evidence that newly-released documents relating to the wiretapping of his former campaign adviser Carter Page “confirm with little doubt” that intelligence agencies misled the court that approved the warrant.

But politicians from both political parties said the documents do not show wrongdoing and that they even appear to undermine some previous claims by top Republicans on the basis for obtaining a warrant against Mr Page.

Visible portions of the heavily redacted documents, released on Saturday under the Freedom of Information Act, show the FBI telling the court that Mr Page “has been collaborating and conspiring with the Russian government”.

The agency also told the court “the FBI believes Page has been the subject of targeted recruitment by the Russian government”.

The documents were part of officials’ application for a warrant to the secretive foreign intelligence surveillance court, which signed off on surveilling Mr Page.

Mr Trump tweeted on Sunday on the documents: “As usual they are ridiculously heavily redacted but confirm with little doubt that the Department of ‘Justice’ and FBI misled the courts. Witch Hunt Rigged, a Scam!”

The release appears to undercut some of the contentions in a memo prepared by House Intelligence Committee chairman Devin Nunes earlier this year.

Mr Nunes and other Republicans had said that anti-Trump research in a dossier prepared by former British intelligence agent Christopher Steele and paid for by Democrats was used inappropriately to obtain the warrant on Mr Page.

Carter Page
Carter Page, pictured last year, was a foreign policy adviser to Donald Trump (J Scott Applewhite/AP)

While the documents confirm the FBI relied, in part, on information from Mr Steele to obtain the initial warrant, they also show how the FBI informed the court of his likely motivation.

A page-long footnote in the warrant application lays out the FBI’s assessment of Mr Steele’s history and the likely interest of his backer, adding that despite the political concern, the bureau believed at least some of his report to be “credible”.

Democrat Adam Schiff, a ranking member on the House Intelligence Committee, said the documents detail “just why the FBI was so concerned that Carter Page might be acting as an agent of a foreign power”.

He told ABC’s This Week: “It was a solid application and renewals signed by four different judges appointed by three different Republican presidents.”

Republican Marco Rubio also broke with Mr Trump, saying he does not think the FBI did anything wrong in obtaining warrants against Mr Page.

“I have a different view on this issue than the president and the White House,” Mr Rubio said on Sunday on CBS’ Face The Nation.

“They did not spy on the campaign from anything and everything that I have seen. You have an individual here who has openly bragged about his ties to Russia and Russians.”

On Sunday, Mr Page said on CNN’s State Of The Union: “I’ve never been the agent of a foreign power.”

In a 2013 letter, Mr Page described himself as an “informal adviser” to the Kremlin, but now said “it’s really spin” to call him an adviser.

Mr Page has not been charged with a crime, but he has been interviewed by the FBI and congressional investigators about his ties to Russia.

White House officials have argued that Mr Page, announced by the president in early 2016 as a foreign policy adviser, played only a minor role in the Trump campaign.

Another former campaign policy aide, George Papadopoulos, pleaded guilty last year to charges brought by special counsel Robert Mueller alleging he had lied to the FBI about his Russia contacts. He is now co-operating with Mr Mueller’s expansive probe.