European Union leaders have warned that the UK must honour the principle of free movement of people if it wants to retain access to the single market after it leaves the bloc.
The French and German leaders also made clear that the freedom of movement of EU citizens was non-negotiable.
Immigration to the UK, particularly from poorer EU countries, was a key issue in the referendum campaign.
Some campaigners for Leave sent a clear message that the vote was about controlling immigration levels.
Read more: Brexit: EU says no compromise on freedom of movement - BBC News