BRUSSELS (AP) — The European Union made public Wednesday its plan for negotiating Britain's departure from the bloc, an unprecedented and complex procedure that must be completed in less than two years.

The mandate grants EU Brexit point-man Michel Barnier a remit to discuss the most pressing issues surrounding Britain's exit, but makes it legally impossible for him to discuss Britain's preferred topics like future ties and trade. That can only happen once EU states decide there is enough agreement on issues seen as "strictly necessary to ensure any orderly withdrawal."33

A glance at some of the key sticking points:

CITIZENS' RIGHTS

A top priority is ensuring there will be effective guarantees that the rights of some 5 million people — around 3 million EU citizens living in Britain plus 2 million Britons in Europe — will be protected after Brexit.

The citizens face massive uncertainty on health benefits, pensions, taxes, employment and education.

The agreement will aim to define who they are, what kind of rights should be protected, and guarantee that any qualifications they have like diplomas and certificates are recognized by all parties after the divorce.

MONEY MATTERS

Britain's financial obligations, expected to amount to at least 60 billion euros ($64 billion), must also be settled.

That will involve its commitments to the EU's 2014-2020 budget, as well as ending its membership of EU institutions, banks and funds like the Turkey refugee facility. Other costs include the relocation of the EU's U.K. based medicine agency and banking authority.

The Financial Times newspaper estimates that the bill could hit 100 billion euros, but Britain has rejected paying this amount.

IRELAND BORDER

Another key concern is to keep people and goods moving smoothly across the border between Northern Ireland — which is part of the United Kingdom — and Ireland, an EU member.

The agreement would ensure that nothing is done to undermine the Good Friday peace agreement that ended the bloody decades-long conflict in Northern Ireland. The aim is to avoid "a hard border" with customs controls, especially when products like milk are produced in the north and treated in Ireland.

OTHER THEMES

— The deal should ensure that any goods put on the market before Britain officially leaves — that deadline is set at midnight on March 30, 2019 — can stay on the market in both the U.K. and the EU.

— Any justice or law enforcement procedures between the parties that are still ongoing when the deadline passes must also be able to be completed.

— Arrangements must be made to protect the rights of those living or working on British military bases on the EU island of Cyprus.

— The mandate says the deal should have dispute settlement mechanisms and be enforceable in a way that respects "the autonomy of the Union and of its legal order." In essence, it means that the EU's top court, the European Court of Justice — much maligned in Britain — should be the ultimate arbiter of the accord.