Ashford MP Damian Green says ‘fake news' spread by websites are “feeding an atmosphere of increasing hatred” that could lead to another murder of an MP.

Mr Green, the First Secretary of State, said websites which spread bile had to consider “who is reading it and what are they going to do next”.

The MP, a former journalist and now the Prime Minister’s deputy, said websites that only presented one side of the story risked “feeding an atmosphere of increasing hatred which at the most horrible of extremes led to the killing of Jo Cox”.

She was murdered by a right-wing extremist just days before the EU referendum last year.

Mr Green said: “The point is that our political discourse needs to be better than it currently is, an argument that will not be lost on many people in this room whose livelihoods are under threat from unscrupulous blogs and websites.”

“If mainstream politicians and journalists start to behave like Twitter trolls and then democracy is in danger.”

Stressing that he did not want to return to a deferential system, he told reporters and correspondents at a Parliamentary lunch: “I have no expectation or desire to go back to the era when journalists politely asked prime ministers if they wish to add anything else at the end of an interview.”

“But I do think that we need to respect each other motives, and treat each other’s views with courtesy, whether we are on either side to the Commons chamber or even on either side of the much bigger chasm of politicians and journalists.”

His comments were endorsed by Professor Tim Luckhurst, who heads the Centre for Journalism at the University of Kent.

“Damian Green is right to warn about the dangers posed by fake news.

"He is also right that some of the scurrilous inventions that have been posted online in recent years have provoked extreme reactions. Fake stories and the fury they can provoke pose a real threat to our democracy.”

“Now, unregulated and irresponsible posts on social media and extremist websites endanger our national conversation.”

But one of the leading ‘alt-right’ websites said Mr Green was wrong.

Raheem Kassam, a spokesman for Breitbart London, said: "For Downing Street to roll out one of the government’s top dogs is proof of how terrified they are of our continued exposure of Theresa May’s track record of failure, on Brexit, on law and order, and on tackling radical Islam.”