Lord Frost, who led negotiations with the EU, quit with immediate effect on Saturday night following “concerns about the current direction of travel” of the Government. In a statement, Lord Frost insisted "Brexit is now secure", but added: "The challenge for the Government now is to deliver on the opportunities it gives us.”

       Brexiteer and former Brexit Party MEP Ben Habib described Lord Frost’s departure as a “seismic resignation”.

       He told Express.co.uk: “Instead of leaving the regulatory nightmare that is the EU he has gilded the lily and made the UK an indebted bloated public sector dominated economy with the highest taxes since the Post War period.”

       He added: “But the person who really needs to leave office is the Prime Minister himself."

       Martin Daubney, Deputy Leader of the Reclaim party, who ran as a candidate in the recent North Shropshire by-election, claimed Mr Johnson has “lost the plot and the direction on travel on Brexit, Northern Ireland and fishing”.

       He said: "Boris Johnson must go."

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