The country’s five main business groups have issued a strongly worded warning about the risks posed by a no-deal Brexit, saying many firms are now reaching “the point of no return”.
Contingency plans are being put in place for the UK leaving the EU without a deal, which are a “significant drain” on companies’ time and money, the Government was told.
Leading business groups said they had watched the ongoing political rows in Westminster "in horror", saying they had only served to increase the risk of a no-deal Brexit.
The British Chambers of Commerce, CBI, EEF, Institute of Directors and Federation of Small Businesses said it was "not a credible proposition" that no deal could be "managed".
They added that firms are pausing or diverting investment that should be boosting productivity, jobs and pay.
A joint statement from the groups said: “Businesses have been watching in horror as politicians have focused on factional disputes rather than practical steps that business needs to move forward.
“The lack of progress in Westminster means that the risk of a no-deal Brexit is rising.
“With just 100 days to go, the suggestion that no deal can be ‘managed’ is not a credible proposition.
“Businesses would face massive new customs costs and tariffs. Disruption at ports could destroy carefully built supply chains.
“From broadcasters, to insurance brokers, to our financial services – the UK’s world-leading services sector will be needlessly disadvantaged, and many professional qualifications will be unrecognised across the EU.
“UK and EU nationals working abroad will be left in deep uncertainty about their future.
“As a result of the lack of progress, the Government is understandably now in a place where it must step up no-deal planning, but it is clear there is simply not enough time to prevent severe dislocation and disruption in just 100 days.”
The business groups added that responsibility for finding a way forward now rests with MPs, urging them to talk to local businesses over the festive break to help realise that the future course of the economy is in their hands.