Germany's European Affairs minister has called for Britain to win "a special status" following Brexit, while calling for talks to begin early next year.
Theresa May has repeatedly stated that she will not activate Article 50, which gives the UK two years to secure new terms, until 2017.
And Michael Roth has told Reuters the UK should be ready to negotiate – and trigger mechanisms to leave the EU – early next year.
"Until the end of the year should really be sufficient time to get organized and adjust to the new situation," he said.
Roth, a member of the Social Democrats which are a junior partner in Angela Merkel's ruling coalition, added that Britain should be granted a position distinct from that of Switzerland and Norway, which have both been cited as potential examples for the UK to follow.
"Given Britain's size, significance and its long membership of the European Union, there will probably be a special status which only bears limited comparison to that of countries that have never belonged to the European Union," he said.
"I want relations between the European Union and Britain to be as close as possible," he said.
However, pressed on whether that would mean granting UK access to the single market while limiting free movement, Roth said: "I can't imagine that."
"The free movement of workers is a highly prized right in the European Union and we don't want to wobble on that."