Three European Union cities have pulled out of the race to host the European Medicines Agency (EMA) ahead of a secret ballot later on Monday to choose its new home as Britain prepares to leave the bloc.

Hosting the EMA and the smaller European Banking Authority (EBA), both currently based in London, will mean jobs, business euros and prestige, so competition has been tough, though there have also been signs of regional solidarity in the contest.

Malta withdrew from the race to host the EMA on Friday and Croatia and Ireland followed suit on Monday, leaving 16 EU cities competing to host the EMA. However, Dublin is still among eight cities competing to host the EBA.

The two winners - whichever country wins the EMA will not be allowed to seek the EBA - will be picked on Monday in a series of votes so complex that it is hard to predict the result. They are due to start around 1500 GMT.

Estonia's EU minister Matti Maasikas, who will chair the voting session, called the contest "a sad reminder of the concrete consequences of Brexit". Britain is due to leave the EU in March 2019.

Despite fierce competition, the 27 EU states - minus Britain - are keen to avoid any protracted and bruising dispute over the matter as they see preserving unity as essential in facing Brexit, the biggest setback in the post-World War Two history of European integration.

"Whatever the outcome, the real winner of today's vote is EU27. Organised and getting ready for Brexit," EU chairman Donald Tusk tweeted ahead of the vote.

Italian EU Minister Sandro Gozi said Milan - a clear favourite in online betting - was a good candidate for the EMA but added that it was "impossible to say" how the vote would go.

Italy is counting on support from its southern EU peers. In another sign of regional solidarity, Belgium's foreign minister said Amsterdam would make a good pick, even though Brussels is itself in the running for both agencies.

The Czech Republic's EU minister, Ales Chmelar, said Prague, a candidate to host the EBA, expected at least one of the two bodies to move to less-developed, ex-communist eastern Europe, where the Slovak capital Bratislava is also a strong contender for the EMA.