Financial services companies have moved assets worth $1 trillion from the U.K. to the rest of Europe since the Brexit referendum, a new study from audit firm EY estimates.

In a report published Monday, the consultancy said its "Brexit Tracker" estimated financial services firms had moved almost £800 billion ($1.02 trillion) out of Britain since the 2016 vote.

However, EY acknowledged that this was a "conservative" amount in relation to the size of the U.K.'s financial sector.

"This number is still modest given total assets of the U.K. banking sector alone is estimated to be almost £8 trillion, but may become larger as we move towards Brexit," the research said.

The study tracked announcements from 222 companies in the sector — 20 of which had publicly declared intentions to move operations, staff members and other assets.

Omar Ali, U.K. financial services leader at EY, said the number could grow as the risk of a no-deal Brexit heightened.

"We know that behind the scenes firms are continuing to plan for a 'no deal' scenario. The closer we get to 29 March without a deal, the more assets will be transferred, and headcount hired locally or relocated," he said.

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