French President Francois Hollande on Monday urged Britain to "not waste time" in triggering the process to leave the EU, arguing that it is to all parties' advantage to move forward quickly.

"Being responsible means not wasting time -- not wasting time in dealing with the question of Britain's departure, not wasting time too in putting in place the new stimulus that we need to give to the European Union, that is to say, the 27 members," he said after talks in Berlin with Italy and Germany's leaders. 

"Because nothing is worse than uncertainty. Uncertainty generates often irrational behaviour. Uncertainty also leads financial markets to act irrationally."