Sinn Féin has accused the British Government of "playing reckless games" over Brexit.
South Antrim MLA Declan Kearney made the remarks after a report concluded that the government's approach to post-Brexit trading arrangements in Northern Ireland has left businesses in the dark.
The report by the Northern Ireland Affairs Committee also condemned the government for leaving businesses ill-prepared for the end of the Brexit transition period on December 31.
Mr Kearney claimed that the government is "neither properly focused upon, or concerned about" addressing concerns by businesses about the "lack of detail" to continue trading under the new procedures governing the EU and British Government Withdrawal Agreement.
"I am not surprised this British parliamentary affairs committee remains to be convinced the current British Government fully understands its political approach provides neither the clarity nor the detail required by the business community in the north," he said.
"This has been apparent for some time and is a damning indictment of the Tories' Brexit agenda, and failure to deliver on the terms of the Irish Protocol."
Mr Kearney also criticised the government for not seeking an extension of the transition period in June as "absolutely wrongheaded".
"That decision is further evidence the British government is preparing for a 'no deal Brexit'. Such an outcome would be a catastrophe for our local businesses, and the regional and island economies," he added.
SDLP MP Claire Hanna, who sits on the NI Affairs Committee, was also critical of the government, and warned that businesses based in the north will face additional barriers to trade with Britain if no action is taken to secure the promised "unfettered access" to the GB market.
"The report published by the Northern Ireland Affairs Select Committee today reflects on the failure of Boris Johnson's government to engage with the fundamental contradictions of their position," she said.
"To continue to boast about unfettered access to the GB market for Northern Ireland businesses, for example, without addressing the need for export and exit summary declarations under EU customs rules is fundamentally dishonest.
"If this government applied the same energy and resource to solving these problems for local businesses as it does to sloganeering ad campaigns, we may be in a better position. As it stands, there has been no indication that the needs of people and businesses in Northern Ireland are a priority, and that needs to change."
Responding to the report, a British government spokeswoman said: "We are engaging intensively with businesses and the Executive in Northern Ireland and will set out further guidance later this month."
