"#Brexit: 2,500 jobs already announced for Ile-de-France, with a target of 10,000 by 2019," Valerie Pecresse tweeted on a visit to London to meet representatives of 70 internationally-focused companies based in London.
Pecresse's figure concerns large financial companies, so the total could be closer to 3,500 and 4,000 posts once small businesses are taken into account, Arnaud de Bresson, chief executive of financial lobby group Paris Europlace and who was part of the visit, told AFP by telephone.
Large financial institutions, including British bank HSBC, Swiss peer UBS and US giants JPMorgan and Morgan Stanley, have confirmed plans to move some activities to Paris, as well as to Amsterdam, Dublin and Frankfurt, as a result of Britain's departure from the European Union.
The Bank of England said this month that 10,000 UK financial services jobs could move abroad on the first day of Brexit, after warnings of up to 75,000 relocations in total.
Britain is set to leave the bloc in March 2019, but remains locked in tough exit negotiations with the EU.
The French government is eager to do what it can to make the most of the fallout of Britain's divorce from the EU.
In September the French government confirmed it plans to cut taxes on high-earning finance sector jobs as part of efforts to make Paris more attractive for firms shifting operations out of London due to Brexit.
The 2018 budget will eliminate the marginal tax rate on salaries of employees in firms not subject to the Value Added Tax (VAT), such as banks and insurance companies, that exceed 152,279 euros ($178,761).
From January 1 the higher 20 percent rate on wages above that level will disappear and the 13 percent rate applied until 2013 will be used.
The government estimates that banks, insurance companies and other financial firms stand to save 140 million euros in 2018, thanks to the change.
But it's not just financial companies who look set to leave London for Paris.
Successful startup Once told The Local the uncertainty around Brexit and the election of pro-business Emmanuel Macron in France meant the time was right to swap London for Paris.
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