The FBI is investigating possible links between US President Donald Trump's election team and the Russian government, Director James Comey told the House Intelligence Committee on Monday.

The intelligence agency is investigating Russian government interference in the US election and any links or cooperation between the Trump campaign team and Moscow, Comey told the panel, taking the unusual step of confirming an ongoing investigation.

The investigation is classified and Comey said he would not reveal more about the investigation or whom it is investigating.

Congressman Devin Nunes, a California Republican and chairman of the committee, said the panel aimed to get to the bottom of Russian actions and whether anyone from a political campaign conspired with them.

He also said the panel would look at allegations of "improper surveillance" after Trump charged that former president Barack Obama had order the wiretapping of his offices.

Nunes said lawmakers "know there was not a physical wiretap of Trump Tower," but said it was possible that other techniques were used against Trump and his associates.

Comey confirmed there was "no information" to support Trump's claims that the FBI wiretapped his offices.

"I have no information that supports those tweets and we have looked carefully inside the FBI," he said. "The Department of Justice has asked me to share that the information is the same for the department and all its components."

Comey said it was outside the power of the president to order a wiretapping of any US citizen.

In a more than five-hour hearing, Republicans on the committee focused on the damage caused by intelligence leaks, while Democrats focused on the Trump-Russia ties.

Nunes urged Comey to conduct a quick investigation because it was casting "a big, gray cloud that you've put over people who have very important work to do leading this country."

The White House however stood its ground, insisting there was no evidence Trump's team colluded with the Russians and that the president would still not withdraw allegations that Obama had ordered him to be surveilled.

"Investigating it and having proof of it are two different things," spokesman Sean Spicer said, noting the ongoing hearing in Congress was just the first of many.

Using his official government Twitter account, Trump had tweeted selective video clips from the hearing, claiming they showed "Russia did not influence the electoral process."

Comey however was asked about the reading during the hearing and declared it to be a misreading of his comments.

Trump had earlier weighed in before the hearing got underway to deny Russian meddling in the 2016 US elections.

"The Democrats made up and pushed the Russian story as an excuse for running a terrible campaign," Trump wrote on Twitter.

US intelligence agencies last year declared that hacking against Democratic Party organizations, which led to leaks of embarrassing information about the left-leaning party and its presidential nominee, Hillary Clinton, was likely directed by the highest levels of the Russian government.

Admiral Mike Rogers, head of the National Security Agency, told the panel that the intelligence community stands by that assessment.

The furore about the claims has mushroomed in recent months, with allegations that Russian officials held sway over Trump's campaign dogging his young administration for weeks now.

Those charges have proven hard to shake, given that Trump's first national security advisor, Michael Flynn, resigned after it emerged that he lied about contact with Russian officials before entering office.

Similarly, US Attorney General Jeff Sessions has been accused of lying about meetings with Russian officials.

But Trump, in his tweets, stood firm, noting that former director of national intelligence James Clapper said during a televised interview Sunday that he was not aware of any evidence linking Trump or his team to Russia.

"James Clapper and others stated that there is no evidence Potus colluded with Russia. This story is FAKE NEWS and everyone knows it!" tweeted Trump.

The president argued instead that the true problem is that so much information about the inner workings of his administration are being leaked to the media.

"The real story that Congress, the FBI and all others should be looking into is the leaking of classified information. Must find leaker now!" he tweeted.

As president, Trump has the authority to direct the FBI to launch such a probe.

Related stories

Latest news

Hong Kong elects pro-Beijing candidate Lam; activists vow opposition

Carrie Lam, formerly Hong Kong's second-highest-ranking official, was voted in to the island's top spot Sunday by a small circle of electors, a move that raises the spectre of further tensions between authorities and pro-democracy activists.

Indian girl alleges gang rape by eight school teachers

Indian police are investigating allegations of gang rape and blackmail against eight teachers at a private school in western India.

Thousands of Yemenis protest against Saudi forces on war anniversary

Thousands of Yemenis gathered in rebel-held Sana’a on Sunday to protest the fact that it's been two years since Saudi Arabian forces began an air campaign in support of a government that was ousted from the capital years ago.

Hamas closes border with Israel after senior figure killed

The Islamic Hamas movement on Sunday closed the border between the Gaza Strip and Israel, in a sign of growing tensions after the assassination of one of Hamas' senior figures.

Pentagon: US airstrike in Afghanistan kills al-Qaeda leader

Qari Yasin, an al-Qaeda leader, was killed in a US airstrike in Afghanistan earlier this month, the Defence Department in Washington said Saturday.

IS claims credit for Bangladesh blasts as death toll rises to six

The Islamic State militant group has claimed responsibility for bomb blasts near a suspected militant hideout in Bangladesh, according to a report, while police said on Sunday that the death toll from the explosion had risen to six.

Bulgarians vote in new snap poll as EU, Russia and Turkey watch

Voting began Sunday in Bulgaria's third snap parliamentary election since 2003 amid expectations that it would once again result in a fragmented parliament.

Serbian politics blindsided as white jester grabs nation's attention

He mocks everything, including himself. He is not even real. Yet Ljubisa Preletacevic Beli is the runner-up in popularity polls ahead of Serbia's April 2 presidential elections.

One reported dead in shooting on Las Vegas Strip

One person was dead and another injured after a shooting on the Las Vegas Strip Saturday, police said, according to media reports, just hours after burglars hit a popular casino hotel.

Andorra end run of 58 defeats in 0-0 draw with Faroe Islands

Football minnows Andorra played to a 0-0 draw against the Faroe Islands in World Cup qualifying on Saturday to end a run of 58 straight defeats in competitive games spanning almost a dozen years.

Croatian PM: Government's aim is Agrokor's long-term sustainability

Prime Minister Andrej Plenkovic said on Saturday that the government's aim was for the Agrokor food company to ensure, if possible, liquidity and a restructuring plan on its own as well as long-term sustainability.

East African countries pledge to integrate Somali refugees

East African leaders on Saturday pledged to facilitate the free movement of Somali refugees in their countries, calling for alternatives to camps for the refugees, whose number stands at about 900,000 in the region as well as Yemen and Egypt.

Demonstrations erupt at funeral procession in Bahrain

Dozens of protesters marched on Saturday in northern Bahrain at a funeral procession for an 18-year-old, who died after he was shot during a raid by security forces.

Rights group: Hundreds arrested in Belarus anti-government rallies

Hundreds of people including dozens of journalists were arrested across Belarus on Saturday as the country staged its annual anti-government rallies, human rights group Viasna said.

Iraq, US to investigate Mosul civilian killings

The United States and Iraq said on Saturday they would investigate reports that hundreds of civilians have been killed during the fight to retake Mosul from the Islamic State extremist group.

Rallies across US as Trump licks wounds from healthcare defeat

Supporters of US President Donald Trump planned marches of varying sizes in cities across the country on Saturday.

Erdogan says he accepts that death penalty could block Turkey from EU

Turkish President Recep Tayyip Erdogan said he accepted that reintroducing the death penalty could put an end to his country's bid to join the EU, as he continues to campaign for a referendum on expanding his powers.

Militiamen execute 42 police officers in central Congo

Militia fighters in central Congo have killed 42 police officers and abducted six others in an ambush, a provincial parliamentary officer said Saturday.