FRANKFURT (Reuters) - Europe’s drugs regulator warned on Tuesday it could lose more than 70 percent of it staff, making it unable to function, if politicians pick the wrong new home for the London-based agency.

FILE PHOTO: The headquarters of the European Medicines Agency (EMA), is seen in London, Britain, April 25, 2017. REUTERS/Hannah McKay

Citing a staff survey, the European Medicines Agency (EMA) said anywhere between 19 percent and more than 70 percent of employees plan to leave when the regulator moves due to Britain’s departure from the EU - depending on the new location.

“The future of public health in Europe is at stake,” the EMA said in a statement.

The European Commission is assessing potential new locations for the EMA, but the decision rests with EU leaders who will try to reach a deal at their next summit in October. A final decision is expected a month later.

An EMA spokeswoman said the full survey results had been passed on to the EU Commission. The survey asked respondents their views on 19 cities but the spokeswoman declined to name them.

Milan, Copenhagen, Athens, Amsterdam and Barcelona are among the cities seeking to host the EMA, with Milan seen as a possible frontrunner.

“For certain locations staff retention rates could be significantly less than 30 percent. This would mean that the Agency is no longer able to function and, as there is no back-up, this would have important consequences for public health in the EU,” the EMA said.

For the five most popular locations, staff retention rates would range between 65 and 81 percent, allowing for approval of new drugs and safety monitoring to largely continue, but with possible delays in some initiatives such as tackling antimicrobial resistance, the agency said.

Still, it would take two or three years to fully recover from the move.

If one of the five lower-ranking cities with a projected staff retention rate of 51-60 percent was picked, new drug approval as well as implementation of new legislation would be delayed, the EMA said.

“Public trust in the system” would start to erode, it warned, adding it would then need up to five years to regroup.

The consequences of choosing one of the nine lowest-ranking locations would be even more dire, exposing patients to serious risk due to delays in drug approval and poor safety monitoring, the agency said.

The EMA, with close to 900 staff, said last month it was cutting back on lower-priority work as it prepares for disruption caused by Brexit and the need to relocate from London to another city inside the European Union.

Aspiring host cities have lined up sweetheart deals including free rents, landmark buildings and tailor-made relocation services in a race to house either the EMA or the European Banking Authority (EBA), the other Britain-based EU institution on its way out.