Environment Secretary Michael Gove said ministers were “united” around a transitional Brexit deal to allow continued access to migrant labour and provide economic stability.
Under a plan championed by Chancellor Philip Hammond, European workers will be able to come to the UK for at least two years, with a transition potentially lasting as long as three or four years.
The concession suggests that Britain could stay in the European single market for several years after its departure from the EU.
Business leaders have called on the government to negotiate a transitional period to prevent a dramatic “cliff edge” change in trading terms with the Continent, and instead ease the UK economy into a new economic relationship to be negotiated with the EU.
Mr Gove, a prominent Brexiteer, said the government would take a “pragmatic” approach in response to suggestions Britain could maintain free movement for EU citizens during a transition period following the official separation from Brussels.
He said decisions on an “implementation period” would be made “in the best interests of our economy”.
Fellow Brexiteer Liam Fox said he was prepared to wait “another couple of years” for a full separation from Brussels.
At a speech on post-Brexit environmental policy, Mr Gove said: “I know not just from agriculture but from other industries how important it is we ensure we have access to the high-quality labour on which the success of our economy depends and, as the Prime Minister has made clear, as we leave the European Union we will have an implementation period which will ensure we continue to have not just access to labour, but the economic stability and certainty business requests, and that is something around which the government and the Cabinet are united.”
Mrs May stressed her backing for an implementation period when speaking with business leaders who attended the first of a series of quarterly Downing Street forums on Brexit.
A Downing Street spokesman said: “The Prime Minister reiterated that the government’s overarching goal is for a smooth, orderly exit culminating in a comprehensive free trade deal with the EU, with a period of implementation in order to avoid any cliff-edges.”
One of the attendees at the No10 summit, Francis Martin of the British Chambers of Commerce, made clear a transition period is a priority for business. He said: “Our research shows clear support among the business community for the UK to reach a comprehensive agreement with the EU, and for a transition period which will prevent firms facing a cliff-edge.
“The prospect of multiple, costly, adjustments to trading conditions is a concern for many, so starting discussions on transition arrangements as soon as possible would go a long way to boost business confidence.”