British Chancellor of the Exchequer Philip Hammond has said Brexit means that Britain will leave the EU's single market and the bloc's customs union.
Speaking in an interview on BBC, he said he wanted an exit that would support jobs and investment.
The UK needs a seamless Brexit transition to support jobs and investment by ensuring a new customs arrangement with the European Union that avoids bureaucratic delays to trade, he said.
"When I talk about a Brexit that supports British jobs, British investment and British business I mean a Brexit that avoids those cliff edges," he said.
He said such a Brexit would mean "that we segue seamlessly from the customs union that we are in at the moment to a new arrangement in the future that will continue to allow British goods to flow not just without tariffs, because actually tariffs are a relatively small part of the problem, it is without delays and bureaucracy."
British Brexit minister David Davis heads to Brussels tomorrow to open divorce talks with the EU with a message that there should be "no doubt we are leaving the European Union".
Days after a suggestion from French President Emmanuel Macron that Britain could still choose to remain, Mr Davis said there would be no backtracking from British Prime Minister Theresa May's plan to deliver on Brexit.
"As I head to Brussels to open official talks to leave the EU, there should be no doubt we are leaving the European Union, and delivering on that historic referendum result," Mr Davis said in a statement.
"Leaving gives us the opportunity to forge a bright new future for the UK one where we are free to control our borders, pass our own laws and do what independent sovereign countries do."
Mrs May, under pressure after losing her ruling Conservatives' majority in a botched snap election and over her response to the Grenfell Tower blaze in London, says she wants a clean break with the EU - a strategy some in her party have challenged as risking economic growth.
Mr Davis, a prominent Leave campaigner in the referendum, said he was approaching the talks in a "constructive way", knowing they will be "difficult at points".
"We are not turning our backs on Europe," he said in the statement.
"It's vital that the deal we strike allows both the UK and the EU to thrive, as part of the new deep and special partnership we want with our closest allies and friends."
