* EMA leaving London on Brexit in 2019
* 19 EU cities are bidding to host it
* Vote to be held on Nov. 20 in Brussels
* Diplomats say national interests predominate
By Lily Cusack and Alastair Macdonald
BRUSSELS, Nov 9 (Reuters) - Nineteen EU governments will slug it out in a series of secret ballots in 10 days' time for the right to host the European Medicines Agency (EMA) once it leaves London after Brexit, EU officials said on Thursday.
Confirming that none of the cities, from Porto to Helsinki, has dropped out of the running since the contest was opened some months ago, those organising it confessed they had no idea how long the voting would take during a meeting of the 27 European affairs ministers in Brussels on Monday, Nov. 20.
"It'll be a bloodbath," said one senior diplomat who has taken part in previous such sessions for the prestige and profit of hosting EU agencies. "Everyone will be fighting their corner. It will have nothing to do with the merits of these cities."
In the case of the EMA, whose fate will be decided before a vote the same day among eight cities for the smaller European Banking Authority, the prize is to replace London as a major hub for international pharmaceutical firms and researchers seeking approvals for products, bringing jobs and travel business.
The EMA itself has warned that moving to some of the cities on the list -- sources have said notably those like Warsaw or Sofia in eastern Europe -- would see so many of its 900 London staff quit that it would harm Europe's health. Top choices for employees are Amsterdam, Vienna and Barcelona.
Senior diplomats said that logic may, in the end, count for little. Previous contests have been won by some of those least expecting it, leaving favourites aware that votes pledged to them in the run-up did not end up being cast for them in secret.
Governments have been lobbying their peers for months. Calls by leaders for the choice to be made on impartial and objective grounds have largely gone unheeded. The executive EU Commission gathered bids and distributed them to member states but offered no ranking or analysis of how they rated against each other.
States agreed to a number of criteria, including that cities chosen should offer premises ready for a start in March 2019, when Britain leaves the EU, be accessible from across Europe and take account of "geographical spread" -- the fact newer members in the east host fewer agencies than richer neighbours.
However, with each minister able to cast votes in secret, those criteria may play little role. In the first round, each country can award three points to their first choice, two to a second and one to a third. Diplomats and officials said the top score of most would probably go to their own city, while other points may go to some of the weaker candidates to avoid damaging their own chances.
If there is no winner, the top three will go into a second round and, if needed, there will be a run-off. If that ends in a tie, the Estonian minister chairing the meeting will draw lots. (Editing by Emelia Sithole-Matarise)
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