The number of British citizens seeking French nationality has increased eightfold since 2015, the year before the country voted to leave the European Union, official figures showed on Wednesday.
France's interior ministry said that 386 Britons had asked for citizenship in 2015.
In 2017, the number of applications leapt to 3,173 and a further 1,370 applied in the first six months of 2018.
Britain's membership of the EU currently means its citizens are guaranteed the same rights to work and live as locals.
But Britons voted to leave the bloc in a referendum in June 2016.
“The Brexit context has generated a significant increase in the number of applications by Britons for French nationality,” the ministry said.
Negotiations on Britain's departure from the EU appear to be heading to a dramatic conclusion ahead of the country's exit deadline on March 29, 2019.
Fears are growing of a “no deal” scenario that would see Britain crash out of the bloc without an agreement governing its trade, economic and security ties with its allies in Europe.
The French government has prepared legislation set to be debated in parliament in November that would clarify the legal rights of the estimated 150,000 to 300,000 Britons who have settled in France.
Most of them are retired, with the largest number settled in rural areas of the wine-rich southwestern region of the country, statistics agency Insee said last year.
Over the past two years, the percentage of British applications for French nationality has gone from 0.4 percent of the total number of applications to 3.5 percent, the ministry added.
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