LONDON: Prime Minister David Cameron was to meet EU president Donald Tusk at Downing Street on Sunday as negotiations reach a decisive point ahead of a referendum on whether Britain should leave the bloc.

The working dinner comes with Tusk expected to publish draft proposals early this week for how to reform Britain’s relationship with the EU, which Cameron can then use to campaign against a so-called “Brexit.”

British officials hope that a final deal can be nailed down at a Brussels summit being held on February 18 and 19. That could then open the door to a referendum in June.

But Cameron insists he is willing to hold out for as long as it takes to secure the right package of reforms, if necessary delaying the referendum to September or even next year.

Opinion polls currently suggest that Britons would vote to leave the EU by a small margin.

Tusk’s visit comes after Cameron held a hastily-arranged meeting with European Commission chief Jean-Claude Juncker on Friday to try to resolve the British leader’s main concern, reducing the number of EU migrants coming to Britain.