Britain's parliament needs to be recalled immediately to discuss Brexit, the opposition Labour Party's finance spokesman John McDonnell says, after leaked official documents forecast possible food, fuel, and medicine shortages.
Britain has less than 74 days to resolve a three-year crisis that is pitting the country against the EU, its closest trade partner, and parliament against the executive.
The outcome will mark its most significant geopolitical move since World War II.
Prime Minister Boris Johnson says Britain will leave the European Union, with or without a transition deal, on October 31. His calls for the EU to renegotiate the existing exit deal have so far been rejected in Brussels.
That puts Britain on course for an unmanaged exit, which an official assessment published by the Sunday Times said would jam ports, increase the risk of public protests and severely disrupt the world's fifth-largest economy.
McDonnell, the Labour Party's second most powerful man, said that the looming crisis demanded parliament's summer break be brought to an early end.
"There's a need now to bring MPs (members of parliament) back together again because we need time now to really have a proper debate and discussion about this," McDonnell, a close ally of Labour leader Jeremy Corbyn, told BBC radio.
His comments add weight to a demand made on Sunday, signed by more than 100 lawmakers, to recall parliament to discuss what they called a "national emergency".
Parliament is currently not due to sit until September 3, when it will reconvene for a short session before breaking up again to allow for annual party conferences. Lawmakers are already fretting that they do not have enough time to try to stop a no-deal Brexit.
Johnson will make his first foreign trip as prime minister this week, meeting German Chancellor Angela Merkel in Berlin on Wednesday and French President Emmanuel Macron in Paris on Thursday.
He will tell them that the British parliament cannot stop Brexit and that a new deal must be agreed if Britain is to avoid leaving the EU without one.
Labour, which is opposed to a no-deal exit, wants to bring down Johnson's government and form its own emergency coalition under Corbyn's leadership to delay Brexit.
Lawmakers from other parties have dismissed the possibility of Corbyn, a veteran leftist, leading any so-called 'Government of National Unity', preferring either someone else to do the job or else to focus on other parliamentary procedures to block a no-deal.
"I don't see how he (Corbyn) could lead a government of national unity," Dominic Grieve, a rebel lawmaker from Johnson's ruling Conservative Party, told the BBC, adding that other people could lead such a government.
"But I am perfectly prepared to cooperate with him (Corbyn) and indeed with anybody else in the House of Commons to make sure that no-deal, which is being threatened by the current government, doesn't happen," Grieve said.
McDonnell said there was a majority in parliament committed to stopping a no-deal exit, and that Corbyn would meet rival leaders next week to discuss the best approach to doing so.
Johnson's ministers, including Michael Gove, played down the leaked no-deal assessment, saying the document was old and did not reflect the increased funding and planning that the prime minister has undertaken since he took office last month.
They accuse Labour and others who are opposed to a no-deal Brexit of undermining negotiations with the EU, saying that EU leaders will wait to see if parliament can block such an outcome before deciding whether to renegotiate the deal.
Australian Associated Press
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