Boris Johnson has been urged by more than 100 MPs from across the Commons to immediately recall parliament from the summer recess, amid claims of a "national crisis".
The letter, signed by MPs representing every political party in Westminster apart from the DUP, claims that the country is on "the brink of an economic crisis" and that it is "unacceptable" for parliament to wait until next month to sit again amid the threat of a no-deal Brexit.
The Commons is due to return from summer recess on September 3. The Speaker can only recall parliament at the behest of the government.
Tory former ministers Dominic Grieve and Guto Bebb are among the signatories of the letter.
The Westminster leaders of the SNP, Liberal Democrats, Plaid Cymru, Change UK, and the Green Party's Caroline Lucas also backed the call, along with several Labour MPs.
The letter says: "Since the Second World War, Parliament has been recalled multiple times in every decade for a wide range of political, security and economic reasons...
This is a national emergency. There is no mandate for an undemocratic no deal #Brexit. Reckless Johnson + unelected Cummings want to gag our democracy. We have written to the PM to demand he recalls Parliament. RT if you believe @BorisJohnson should #RecallNow pic.twitter.com/VSiLl6sOTw— Luciana Berger (@lucianaberger)August 17, 2019
"Our country is on the brink of an economic crisis, as we career towards a no-deal Brexit which will have an immediate effect on food and medical supplies, damage our economy, jobs, the public finances, public services, universities and long-term economic security.
"A no-deal Brexit also threatens our crucial security co-operation to keep our country safe from criminals and terrorists."
Pleased to join MPs from across the House in signing this letter to demand PM recalls Parliament
This a national emergency. There is no mandate for a reckless No Deal #Brexit. Johnson & Cummings want to gag our democracy
RT if you believe @BorisJohnson should #RecallNow pic.twitter.com/XIvjghuWg1— Caroline Lucas (@CarolineLucas)August 17, 2019
They added: "We face a national emergency, and Parliament must be recalled now in August and sit permanently until 31 October, so that the voices of the people can be heard, and that there can be proper scrutiny of your government.
"A true democrat should not fear such scrutiny. The question is whether you are one."
The letter also criticises Mr Johnson's approach to the Brexit negotiation and claims a "creeping and disturbing populism" is taking over Mr Johnson's discourse with the EU.
Pleased to have signed this letter to @BorisJohnson - there is no political mandate for a reckless no deal Brexit. It would cause huge economic damage to our country- please RT if you believe he should #RecallNow https://t.co/xIdjFR1pJt— David Lammy (@DavidLammy)August 18, 2019
It adds: "As prime minister you have made policy announcements to the media rather than at the dispatch box. Your plans involve the spending of billions of pounds of taxpayers’ cash to back up your reckless no-deal plans.
"You have failed to conduct any substantive negotiations with EU partners. And you have shown utter disregard for the crucial relationship between the UK and the Republic of Ireland. These are grounds in themselves for a recall of parliament."
After the letter was published, #recallnow was trending on Twitter, as MPs shared the letter and made further pleas.