Chambers Ireland has described as irresponsible and reckless the move by the British Government to publish a bill to change the Northern Ireland protocol.
Chief executive, Ian Talbot, said once again businesses must begin planning for a no-deal Brexit.
"Ordinary people across the island simply want to be able to move on with their lives without politicians playing to the party-political gallery," he said.
"The British Government may write platitudes about the 'rules based international order' in the New York Times, but actions like today’s demonstrate how unreliable an actor they can be."
Mr Talbot added that this is no way to conduct business.
"Only the least reliable of counterparties are so fickle and false with their word," he said.
"How can any state expect a genuine relationship with Britain when this is how they act."
The British Irish Chamber of Commerce said it was alarmed by the development by Boris Johnson’s Government which it claimed went against the wishes and best interest of businesses across Great Britain and Ireland.
"It pushes us even further away from a settled solution that will provide long term benefits not just to Northern Ireland but across the two island," said John McGrane, Director General of the organisation.
"We are already seeing the wholly negative consequences of the failure of the UK Government to fully implement the Protocol."
He pointed out that foreign direct investment into the UK has been impacted and the UK frozen out of the European research fund, Horizon Europe.
Mr McGrane said the chamber had put forward some practical ideas that could alleviate the majority of the frictions that have arisen under the protocol including a veterinary agreement, the inversion of the risk principle for non SPS goods and the strengthening of the mandate of the Joint Committee to address any issues.
"The legislation presented in Westminster today jeopardises the economy of Northern Ireland, the second-best performing region in the UK since Brexit, but it also threatens the Trade and Cooperation Agreement and the millions of jobs across Great Britain and Ireland that it has protects," he said.
Meanwhile, Retail Northern Ireland said the British government's unilateral action will make it more difficult to secure a wider agreement which would provide certainty and stability for the local business community.
"The bottom line is - we need an agreed co-designed solution to the challenges around the Protocol involving both the UK Government and EU," said Retail NI Chief Executive Glyn Roberts.
"Retail NI would encourage the UK Government and EU to restart intensive negotiations with a new sense of urgency and for both sides to go the extra mile for an agreement."
