Guy Verhofstadt said: “I have seen many times in politics that a so-called transitional agreement becomes an eternal or definitive agreement, so that has to be avoided.”
Speaking to the BBC, Verhofstadt said any negotiation would have to be concluded by the end of 2018 so that the UK could leave the EU before European Parliamentary elections in 2019.
The process of negotiating trade deals is expected to take significantly longer than two years. Prime Minister Theresa May has spoken about a transitional arrangement to avoid a “cliff edge” if a full trade deal is not completed before the UK government plans to leave the EU in 2019.
Chancellor Philip Hammond on Monday called for a “longer period to manage the adjustment”. He said a transitional deal would be beneficial for both the UK and the EU.
Meanwhile, a House of Lords report due on Thursday has warned 200,000 jobs in the financial services sector could be at stake if there is no transitional deal, according to the Guardian.
Verhofstadt, who was Prime Minister of Belgium from 1999 to 2008, also repeated the idea of associate membership of the EU for British citizens, first mooted last week.
“Many many British citizens will want to continue to have a link to Europe,” he said.
The plan would see individual British citizens given the chance to opt in to remain citizens of the EU and retain the benefits such as freedom of movement. Verhofstadt has said the plan would form a part of the negotiations.