[STRASBOURG, France] Britain should trigger its divorce from the EU as soon as possible and formally leave by 2019, the European Parliament's chief Brexit negotiator Guy Verhofstadt said on Tuesday.
Mr Verhofstadt, a former Belgian prime minister, also warned London that it could only keep access to the prized single market by accepting the free movement of all European Union citizens into Britain.
"The UK should trigger the Article 50 as soon as possible so that we can finalise these negotiations by 2019" ahead of the next EU parliamentary elections that year, Mr Verhofstadt told a news conference at the parliament in Strasbourg, France.
"I cannot imagine that we start the next legislative cycle without agreement, and that we enter a new legislative cycle with no solution," he added.
British Prime Minister Theresa May has said she will not trigger Article 50 - the two-year divorce process leading to an exit from the EU - until early 2017 at the earliest.
She has said London needs more time to finalise its demands, with the government split on how to curb immigration while keeping the benefits of the single market.
But Verhofstadt said there could be little negotiation on this, saying the two concepts were "inseparable".
"The position of the parliament is very clear. The position has always been that if the UK wants to remain part of the single market it will also have to accept the free movement of our citizens," he said.
Mr Verhofstadt, the head of the European Parliament's Liberal group, was appointed last week to lead the legislature's negotiations on Brexit.
The parliament will have a final vote on Britain's deal to leave the EU.
His appointment caused shock in London as he is a diehard European and has been scathing in his criticism of Britain's shock June vote to quit the 28-nation bloc.