Brexit has cost the British financial services sector £3.9 billion ($7.09 billion) since the 2016 referendum, a new report reveals.

The EY report says companies including insurers have spent £1.3 billion ($2.36 billion) on relocation costs, legal advice and contingency plans, and £2.6 billion ($4.72 billion) on capital to enlarge headquarters outside the UK.

Dublin has proven the most popular city for relocations, with 29 companies moving there, while the number choosing Luxembourg has risen to 23 in the past three months. Frankfurt has attracted 22.

Nearly £1 trillion ($1.82 trillion) of assets and 7000 jobs will move to Europe, which has remained unchanged in recent months. Companies paused Brexit planning between March and May as Parliament negotiated an extension to the withdrawal deadline.

EY UK Financial Services Leader Omar Ali says the final sums are likely to be much larger, because only a few businesses have put a figure on potential costs. The number of companies that have confirmed they will quit Britain has risen slightly to 91 out of 222 studied.

“Given the tight timeframes and many unknowns, lots of financial service firms have prepared for a ‘no-deal’ scenario with temporary contingency plans, which are often inefficient and costly,” Mr Ali said. “A more sustainable approach will need to follow once the long-term level of UK-EU market access becomes clearer.”