White House national security adviser Robert O'Brien has denied reports that US intelligence shows Russia is interfering to help Donald Trump win a second term.

But it came with the caveat that he has not looked at or sought out materials related to those reports.

He told ABC News chief anchor George Stephanopoulos that it was a "non-story" adding: "I haven't seen any intelligence that Russia is doing anything to attempt to get President Trump re-elected."

The interview comes shortly after reports emerged that the Office of the Director of National Intelligence told politicians that Russia is meddling in the 2020 race, and trying to put a finger on the scale for the Trump campaign.

But Mr O'Brien said: "I think it's the same old story we've heard before.

Vladimir Putin: A decade of photo-ops for Russia's man of steel Show all 20 1 /20 Vladimir Putin: A decade of photo-ops for Russia's man of steel Vladimir Putin: A decade of photo-ops for Russia's man of steel Russia's Prime Minister Vladimir Putin takes part in a judo training session at a sports complex in St Petersburg on 22 December 2010 AFP/Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin holds a tommy gun during a visit to Izhevsk Mechanical Works, a weapons manufacturer in May 2010 AFP/Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin plays with his dogs Buffy (L) and Yume at his residence in Novo-Ogariovo in March 2013 AFP/Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin wears a helmet and the uniform of the Renault Formula One team before driving a F1 race car on a special track in Leningrad region outside St. Petersburg on in November 2010 Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin sports a pair of goggles during a visit to the Technology Park of the Novosibirsk Academic Town in February 2012 Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin holds a huge pike fish, after he caught it in the Tyva on 26 July 2013 AFP/Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin inspects a horse in the Karatash area, near the town of Abakan in March 2010 AFP/Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin looks down the sight of a replica kalashnikov rifle at a target range in Moscow in April 2012 AFP/Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin works out at a gym at the Bocharov Ruchei state residence in Sochi on 30 August 2015 Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin drives down a highway in St Petersburg in August 2013 AFP/Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin takes part in a judo training session at the Moscow sports complex in St Petersburg, on 22 December 2010. Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin speaks with Leonardo DiCaprio on 23 November 2010 after a concert to mark the International Tiger Conservation Forum in St Petersburg AFP/Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin holds two ancient amphorae he found while scuba diving in Taman Bay as he visits an underwater archaeological site at Phanagoria on 10 August 2011 AFP/Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin caresses a Persian leopard cub as he visits the Persian leopard breeding and rehabilitation centre in the Black Sea resort of Sochi on 4 February 2014 AFP/Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin rides a train in Moscow on 21 November 2019 Sputnik/AFP/Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin hunts fish in southern Siberia in August 2017 Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Russian President Vladimir Putin plunges into the icy waters of lake Seliger during the celebration of the Epiphany holiday in Russia's Tver region in January 2018 AFP/Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin measures a dead polar bear on the island Alexandra Land, part of the Franz Josef Land archipalego in the Arctic Ocean in April 2010 Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin sits inside a T-90AM tank during a visit to an arms exhibition in the Urals town of Nizhny Tagil in September 2011 Getty Vladimir Putin: A decade of photo-ops for Russia's man of steel Putin holds a Bulgarian sheperd dog given to him by his Bulgarian counterpart Boyko Borisov after their press conference in Sofia on 13 November 2010 AFP/Getty

"Our message to the Russians is stay out of the US elections.

"We've been very tough on Russia and we've been great on election security."

During a rally in Las Vegas on Friday, Mr Trump said the Democratic Party had tried to "start a rumour".

"It's disinformation. That's the only thing they're good at, they're not good at anything else."

When pressed on whether it was his duty to get to the bottom of such claims, Mr O'Brien said: "You're basing your assumptions, George, on leaks that came out of a House Intelligence Committee hearing. I haven't seen the intel, and I haven't seen that analysis."

Since it was first revealed that Russia meddled in the 2016 presidential election, US intelligence officials have repeatedly warned about ongoing threats by Russia to interfere in American elections.

Meanwhile The Washington Post has reported that Bernie Sanders has been briefed by US officials about Russian efforts to help his Democratic primary campaign.