The absolute low point for me in more than 30 years of professional life was the Brexit vote.

For all its shortcomings, European co-operation and integration has created an understanding of shared destiny. We no longer point guns at each other; we fight it out at a conference table. And we will continue to do so when the U.K. is no longer a member state but, I hope, still a friend.

The issue of migration has played a key role in all of our member states, wherever we are. Only we, as a European Union, can convince our citizens that we do have an answer to this - not deny migration, not pretend you can solve it by building fences and walls, not pretending we can solve it by letting everybody in.

In a free Europe... the system of power lies on three pillars. These are democracy, rule of law, and human rights. It's impossible to use one against the other.