The government has defended its decision to refuse senior reporters entry to a Number 10 press briefing which led to invited journalists staging a mass walkout.
The head of the civil service has been urged to investigate the "deeply disturbing" decision to order journalists from some of the UK's major news organisations to leave before a briefing on Boris Johnson's Brexit plans on Monday.
Labour leadership hopeful Sir Keir Starmer has asked Cabinet Secretary Sir Mark Sedwill to launch an enquiry and warned that Downing Street risked undermining the integrity of the civil service by inviting selected journalists to a briefing from government adviser on Europe, David Frost.
Cabinet Office minister Chloe Smith insisted that no reporters are barred from "official briefings hosted by the Prime Minister's spokesman".
But she added it was “entirely standard practice” for the Government to host “additional technical specialist briefings, as was the case yesterday".
The journalists excluded included outlets viewed as left-wing or critical of the Government
When correspondents from organisations not on Downing Street's hand-picked list tried to get into the briefing they were told to wait in the entrance hall.
Mr Johnson's director of communications Lee Cain then told them to leave.
When his actions were questioned he told reporters: "We are welcome to brief whoever we want, whenever we want."
The journalists excluded included outlets viewed as left-wing or critical of the Government, although Downing Street sources said it was "clearly nonsense" to claim the decision was made on political grounds.
In protest at the treatment of colleagues from rival organisations, all the journalists present chose to walk out rather than receive the briefing.
Shadow culture secretary Tracy Brabin said: "It is concerning that Boris Johnson seems to be resorting to tactics imported from Donald Trump to hide from scrutiny."
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