Britain turned down the offer to remain a member of the cultural exchange program after Brexit.

The U.K. decided to leave the EU’s Erasmus+ student exchange scheme because Brits’ poor foreign language skills made membership too expensive to justify, a senior British official has revealed.

Lower take-up of the scheme by British students compared to other nationalities — put down to a weak aptitude for language learning — meant London expected to pay in nearly €300 million more a year than it received back, Nick Leake, a veteran senior diplomat at the U.K. Mission said this week.

It comes as youth organizations on both sides of the channel launch a renewed push for the U.K. to rejoin the scheme — and as an EU advisory body urges the Commission to get negotiations going.