When the Brits actually begin the Brexit process, by initiating action under Article 50 of the Treaty of the European Union, it will be the European Council (the EU’s heads of government) with whom negotiations will be conducted, and that body has appointed Didier Seeuws, a Belgian diplomat, The Guardian (in the linked article, describes Mr Seewus as “exceptionally hard-working and combining an impressive grasp of technical detail with considerable political savvy … he is currently director of transport, telecommunications and energy at the European council … [but] … Seeuws was also Belgium’s deputy ambassador to the EU and is credited with negotiating a breakthrough on the European patent system, an issue that had been deadlocked for more than 30 years.“
But no one expects that Jean-Claude Juncker and the European Commission are going to sit, passively, on the sidelines, and M Junker has appointed his own man, Michel Bernier, to, according to The Economist, r”un a Brexit task force inside the European Commission.” Mr Bernier has been described as, amongst other things, “no friend of the City of London,” and his appointment has been described, according to The Economist, as a “declaration of war,” by some of the pro-Brexit tabloids. But both The Economist and the Financial Times describe M Bernier as smart, tough, very good a dealing with complex financial services issues, and, while very pro-EU, a bit of an Anglophile, too.
M Junker, it seems to me, is being both prudent ~ the Commission is certain to need to be involved ~ and a wee tiny bit provocative, but I think his provocation is aimed towards the European Council, not at the UK, because, as The Economist points out, in the bigger scheme of things “Mr Barnier’s views” [and those of M Junker] “will count for relatively little next to those of EU leaders like Angela Merkel.“
Mr Junker is all about process; Prime Minister May and Chancellor Merkel are all about practical politics. In the end, I believe, politics will out.