What does the EU want from Brexit?

As negotiations between the UK and the EU hit choppy waters, the Briefing Room asks what does the EU want from Brexit and what would be its bottom line? David Aaronovitch is joined by expert guests including:Pascal Lamy, former EU Trade Commissioner and Director General of the World Trade OrganisationDaniela Schwarzer, Head of the German Council on Foreign RelationsJacek Rostowski, former Minister of Finance and Deputy Prime Minister of Poland