Intercontinental Exchange Inc., the world’s third-biggest clearinghouse, has taken sides in the tussle between the U.K. and some European Union leaders over a key corner of the financial industry.

The U.K. is the world’s largest hub for clearing euro interest-rate derivatives, a vital activity that ensures buyers and sellers of the contracts get paid. London also accounts for 75 percent of euro derivatives trading, some $574 billion a day.

“There is no reason why this should change as a result of Brexit,” ICE said in a document seen by Bloomberg. “Given that the euro is the world’s second-largest reserve currency and as such provides significant benefits for member states, the wider EU and companies trading overseas, any such protectionist move could severely damage confidence in the currency within the global economy.”

The paper comes as the Financial Times, citing an unnamed French central bank official, said Thursday that the EU’s executive arm should change the rules on euro-denominated interest-rate derivatives even before U.K. leaves the bloc. The ICE paper was circulated to EU member states.

Since Britain’s vote to leave the EU, clearing has become a focal point for those aiming to chip away at London’s role as the continent’s financial center. Leaders in France and Germany want the City’s profitable clearing business, arguing that any clearing of euro derivatives should take place within the bloc.

Eoin Treacy's view

Continental Europe has long looked with longing eyes on the City and wondered how they could create a similar ecosystem in Paris, Frankfurt or Rome. The bad news is there is no easy answer. 

London has developed over centuries as a financial hub first as the capital of an empire but then for its security beyond the ability of continental wars to threaten. Securing its position as the centre of Euro trading was practically a fait accompli rather than a serious matter of discussion and there is no reason to expect its membership of the EU will change that. 

There is another important aspect to London that is simply not present on the continent and that is the lingua franca is English which also happens to be the most important trading language in the world.