Czech state secretary for EU affairs Tomas Prouza warned that the UK would not be allowed to cherry-pick the best elements of membership of the bloc.
Meanwhile, Italian prime minister Matteo Renzi told Sky News that he was “not interested in the consequences” for the UK from Brexit, but Europe would have to “write a new page for the future”.
Mr Prouza said there could be no deal in which the UK tried to separate the basic freedoms of movements of goods, services, capital and labour - effectively meaning Theresa May would have to accept free movement of people as a condition of single market access.
“There is no way whatsoever for the UK to have the cake and eat it at the same time,” he told Bloomberg.
“I see exactly zero chance of success if the UK wants to create first- and second-class citizens in Europe or if it tries to separate the four basic freedoms of movement.”
Meanwhile, Mr Renzi, speaking at the United Nations in New York, said: “Brexit is Brexit, no problem for us.”