French President Emmanuel Macron said he hoped the UK wanted a "common destiny" with Europe but that British leaders had to decide the post-Brexit model they wanted to pursue.
He said the UK could not successfully chase three separate paths – a low-tax or no-tax Singapore-style economy, America's best friend, and the EU's closest ally – at the same time.
Mr Macron, speaking to a small group of international journalists, also suggested geography would trump trans-continental ambitions.
"What politics does Great Britain wish to choose? It cannot be the best ally of the US, the best ally of the EU and the new Singapore … It has to choose a model," he said.
"If it decides on a completely transatlantic policy then we [the EU] will need clarification, because there will be divergence on rules and access to markets.
"If it decides to be the new Singapore, which it has once suggested … well, I don't know. It's not for me to decide, but I would like good, peaceful relations."
The interview took place as the first political clashes of the new post-Brexit era occurred over coronavirus vaccines.
The EU briefly attempted to blockade vaccines from being exported into the UK at the open Ireland-Northern Ireland border before backtracking on its announcement.
Since the Brexit deal came into force at the start of January, exporters and shoppers have been surprised at some of the new tariffs.
Mr Macron said he hoped for a "common destiny" with the UK.
"Our destinies are linked, our intellectual approach is linked, our researchers and industrials work together … I believe in a sovereign continent and nation states; I don't believe in neo-nationalism," he said.
"I am for common ambition and a common destiny. I hope Boris Johnson is also on that path, because I think the British people are. We remain allies.
"History and geography don't change, so I don't think the British people have a different destiny to ours."
