They raised the alarm of “further economic pain” and “falls in investment” after the Government unveiled its deeply controversial Northern Ireland Bill.
Richard Burge, chief executive of the London Chamber of Commerce and Industry, said: “We are hugely concerned that the introduction of the Government’s Northern Ireland Bill risks significant harm to businesses in London and right across the whole of the UK.
“Getting Brexit done was at least meant to deliver certainty to businesses after years of waiting for clarity on the future of the UK’s trade relations with the European Union.
“The introduction of this bill means we are now teetering on the brink of a trade war with the EU and that will mean further economic pain and falls in investment.”
Video: CBI chief: Government can avert recession (Sky News)
His warning came after the Centre for European Reform think tank estimated that Brexit has already dealt a £31 billion blow to Britain’s economy.
The Treasury is refusing or unable to publicly put any figures on the harm being caused by quitting the European bloc.
Mr Burge also highlighted a forecast by the Organisation for Economic Development and Co-operation that the UK’s economy will grind to a halt next year and be the worse performing of G7 nations (the US, UK, Germany, France, Japan, Italy and Canada).
He added: “While the protection of the UK internal market is important, it is equally as important to have macroeconomic stability, especially during this cost of living and cost of doing business crises.
“We urge the Government to carefully consider the impact that playing politics with the Protocol could have on the British economy.”
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