UK businesses feel a "growing sense of urgency" for a Brexit transition deal, the head of Britain's largest business lobby group said on Monday.
"This is real, this is urgent and a transition agreement by the end of the year would help enormously to keep investment and jobs in the country," Carolyn Fairbairn, director general of the Confederation of British Industry (CBI) said in comments to the BBC.
UK businesses are concerned that Britain's planned exit from the European Union in March 2019 could involve an abrupt change in the trade relationship with the continent or a potential no-deal scenario involving heavy tariffs on exports and imports.
Brexit "is tomorrow for many firms and they are making plans now in response to what might be WTO rules which could mean tariffs on food," Fairbairn told the BBC, calling for a "one-step transition deal".
No deal on post-Brexit trade terms would mean reverting to World Trade Organization (WTO) tariffs.
Five major business groups including the CBI and Federation of Small Businesses have written a draft letter intended for Brexit secretary David Davis, calling for a swift and barrier-free transition deal.
It has not yet been decided if the letter should be made public or kept private, a source from within the CBI said, but it will act as preparatory draft for a meeting of business leaders with government at a Business Advisory Council on Wednesday.
The letter echoes warnings by outgoing London Stock Exchange Chief Xavier Rolet on Wednesday that British finance firms will move business to EU countries if Britain fails to hammer out a post-Brexit transition deal by Christmas.
Prime Minister Theresa May has backed a two-year transition period to ease its impact on the economy but she is beset by divisions within her own Conservative party and talks with Brussels are stalled over the size of the UK's exit bill.
Downing Street said the details of the "implementation period" would have to be discussed alongside the final trade deal.
"The implementation period is a bridge to where we are headed in terms of the future relationship with the EU," the prime minister's official spokesman said.