President Donald Trump slammed the idea that his campaign colluded with Russia in a flurry of tweets hours before FBI Director James Comey appears before a House panel. Picture: AP.

He also rejected President Trump’s extraordinary and unproven claim that former President Barack Obama ordered a “wire-tap” on Trump Tower.

“With respect to the president’s tweets about alleged wire-tapping directed at him by the prior administration, I have no information that supports those tweets,” Mr Comey told the House Intelligence Committee on Monday, under questioning from the committee’s top Democrat, Adam Schiff.

He said that no individual can order surveillance of an American, saying only courts can grant this permission after a rigorous application process.

Mr Comey and National Security Director, Admiral Mike Rogers, were called on to testify in a congressional hearing examining potential Russian links to the US election campaign and claims that Trump Tower was “wire-tapped”. It is the most extensive public investigation of matters that have dogged the Trump administration in its first two months.

FBI Director James Comey has confirmed there is no evidence to support Donald Trump’s wire-tap claim. Picture: AP Photo/J. Scott ApplewhiteSource:AP

In his opening statement, Mr Comey acknowledged that the FBI does not ordinarily discuss ongoing investigations, but said he’d been authorised to do so given the extreme public interest in this case.

“This work is very complex, and there is no way for me to give you a timetable for when it will be done,” Mr Comey said.

Admiral Rogers testified that the intelligence community stands behind its January assessment that it is highly confident Russia interfered in the 2016 election with the goal of electing Mr Trump.

He said that his agency is working to provide Congress the material it needs to investigate the intelligence agencies’ findings.

FBI Director James Comey (left) and National Security Agency Director Mike Rogers (right) testify on Capitol Hill in Washington DC. Picture: AFP/Nicholas KammSource:AFP

NUNES: OTHER SURVEILLANCE COULD HAVE BEEN USED

The chair of the House committee investigating President Trump’s accusations of wire-tapping at Trump Tower said other means of monitoring may have been used.

“Let me be clear: we know there was not a wiretap on Trump Tower, it’s still possible that other surveillance activities were used against President Trump and his associates,” Representative Devin Nunes said in a statement opening Monday’s hearing.

It comes a day after he said there “never was” evidence of wire-tapping.

“If you take the president literally, it didn’t happen,” he told Fox News Sunday. “Was there a physical wiretap of Trump Tower? No, there never was, and the information on Friday continues to lead us in that direction.”

US Representative Devin Nunes says there is no evidence that Barack Obama wiretapped Trump Tower. Picture: AFP/Getty/Win McNameeSource:AFP

TRUMP HITS OUT AT RUSSIA COLLUSION CLAIMS

Hours before the hearing, President Trump slammed claims his campaign colluded with Russia in a series of tweets.

Mr Trump said Democrats “pushed the Russian story” to cover up for their poorly-run presidential campaign.

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He then tweeted that the focus should be on finding the individuals who are leaking classified information.

HEARING BEGINS FOR SUPREME COURT PICK

The chairman of the Senate Judiciary Committee praised President Trump’s Supreme Court pick on Monday for an “unfailing commitment” to the principle of separation of powers, as Judge Neil Gorsuch’s confirmation hearing got underway.

“His grasp on the separation of powers — including judicial independence — enlivens his body of work,” Senator Chuck Grassley said in opening remarks to begin the long-awaited hearing 13 months after Justice Antonin Scalia’s death created a vacancy on the Supreme Court.

The court opening was never filled last year as Republicans blocked President Obama’s nominee, Judge Merrick Garland, until a new president could be elected.

Neil Gorsuch takes part in a Senate Judiciary Committee confirmation hearing as US President Donald Trump's nominee for the Supreme Court. Picture: AFP/Tasos KatopodisSource:AFP

Senate Democrats remain furious about that GOP obstruction, and are under intense pressure from liberal base voters opposed to Trump, but they enter the hearing divided over how hard to fight his court choice.

“I’m deeply disappointed it’s under these circumstances that we begin these hearings,” the top Democrat on the committee, Senator Dianne Feinstein of California, said in her opening remarks, referencing Garland’s treatment.

Still, she said senators’ responsibility through the hearing was to determine whether Gorsuch is a “reasonable mainstream conservative, or is he not.”

Gorsuch, 49, is a respected, highly credentialed and conservative member of the Denver-based 10th US Circuit Court of Appeals.

TRUMP’S APPROVAL RATING IN FREE FALL

President Trump’s approval rating has taken a nosedive, according to the latest Gallup poll.

Only 37 per cent of respondents approve the job the president is doing — the lowest level since he took office — while 58 per cent disapprove, the poll found.

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Mr Trump’s approval rating was 45 per cent a week earlier.

Other presidents have experienced even lower ratings, but Mr Trump is the first commander-in-chief in at least 70 years to have dropped this low by March of his first term, according to Gallup.

BISHOP TO TRAVEL TO WASHINGTON DC

With the hearing in full swing, Foreign Affairs Minister Julie Bishop will travel to Washington DC today to attend a meeting of foreign affairs ministers on the fight against IS.

It will be her second meeting with US Secretary of State Rex Tillerson.

Ms Bishop told MPs in Question Time the Australian government had concerns that an estimated 500 foreign terrorist fighters could return to the Asia-Pacific region once the fight against IS was over.

Julie Bishop will meet with US Secretary of State Rex Tillerson for the second time. Picture: AAP/Lukas CochSource:AAP