Politicians are being blasted for "letting British business down" over their handling of Brexit.
A business leader said Parliament had spent three years "going round in circles", leaving companies and communities facing "mass disruption".
Dr Adam Marshall, director general of the British Chambers of Commerce (BCC), said businesses were "angry and frustrated" at Westminster.
In a speech to the BCC's annual conference in London, he will accuse politicians of focusing on "soundbites not substance" and of "listening without hearing".
He will say: "Too many critical questions remain unanswered. No-one would run a business like this, and it is no way to run a country.
"It cannot be right that we leave in a way where government itself predicts there will be mass disruption to businesses and communities.
"It cannot be right that some in Westminster shrug off the possibility of shortages that could affect the well-being and the jobs of many people.
"A messy and disorderly exit would not just be deeply irresponsible, it would be a flagrant dereliction of duty.
"But we in business must make it clear that our elected representatives cannot keep chasing rainbows.
"Like all of us in business, they need to start making tough decisions, however personally or politically difficult they might be.
"Because all of us in business want to move on from this and get back to talking about creating the best possible environment for businesses to thrive, in every part of the United Kingdom."
Dr Marshall will call for the UK's "hard won" international reputation as a great place to do business to be restored.