By William Schomberg
LONDON (Reuters) - Most British companies will implement their plans for coping with a disruptive Brexit by December if there is no clarity by then on how Britain will leave the European Union, a survey by a major employers group showed.
The Confederation of British Industry said its findings showed how the lack of a breakthrough in negotiations between London and Brussels was endangering British jobs, investment and economic growth.
"Businesses have displayed remarkable resilience since the referendum, but patience is now threadbare," CBI Director General Carolyn Fairbairn said.
"Negotiators must secure the withdrawal agreement before December to unlock a transition period. The message to politicians on all sides is: 'your actions will echo through generations'," she said in a statement.
The CBI has urged Britain to keep as close a relationship as possible with the EU after Brexit in March next year but British Prime Minister Theresa May has ruled out its favored option of permanently staying in a customs union with the bloc.
May has so far failed to reach a deal with her EU peers on their future trading relationship. Their next summit is due to take place in mid-December although a November meeting might be scheduled if talks progress.
The CBI said 39 percent of the 236 companies it surveyed planned to implement contingency plans -- including job cuts, adjusting supply chains away from Britain and stockpiling -- by November if there was no clarity on Brexit.
A further 24 percent said they would do so by December, while 19 percent said they had already begun to implement contingency plans.
Eighty percent of the firms said Brexit had already had a negative impact on their investment decisions, the CBI said.
The survey was carried out between Sept. 19 and Oct. 8.