The Wall Street Journal spoke with Belgian Prime Minister Charles Michel, who played a significant role in reaching this month’s agreement over a new British relationship with the European Union.

In the interview, we discussed the British referendum on EU membership, scheduled for June 23, Europe’s migration crisis and the terrorism threat. He said some proponents of a British departure from the EU were “dreaming in Technicolor,” he ruled out a second British referendum on exit, he said it was likely other agreements would fall away – such as those allowing British passport control on French and Belgian soil.

This is an edited transcript of the interview, which was conducted in English and French.

What role do you see for yourself and other European leaders in the British referendum?

I don’t want to be involved in the campaign in Britain, it’s not my role. But I was present in the negotiations and it’s important for me to explain what the issues are for the future.