The world's biggest banks pressed policymakers to pass an urgentBrexit fix, to ensure European traders ongoing access to Londonderivatives clearinghouses and avoid rupturing 61 trillion pounds($78 trillion) in contracts.

The industry's top lobbying associations told the EuropeanCommission, the European Union's (EU's) executive arm, that it mustact fast or risk turmoil when the stopgap solution elapses inMarch. The call echoes pressure on the EUfrom the Bank of England, which has said firms might need to movebusiness out of London as early as next month unless there isclarity.

"We respectfully but urgently request the Commission to providethis confirmation well in advance of the end of December 2019," theFIA, which represents banks, brokers, and other firms in thederivatives markets, said in a letter. The International Swaps andDerivatives Association (ISDA), the Association for FinancialMarkets in Europe, and 11 other industry bodies also added theirsignatures.

The groups' members include the biggest derivatives traders inthe world, such as JPMorgan Chase & Co., Goldman Sachs GroupInc., and Deutsche Bank AG. A spokeswoman for the Commission saidit could act quickly and adopt a decision in a short time frame ifneeded.

With the state of Brexit still uncertain and the U.K. in thethroes of an election campaign, the financial industry is pleadingfor continuity in several areas of the markets that don't yet havea Brexit roadmap. The London Stock Exchange Group Plc'sclearinghouse for interest-rate swaps is the world's largest host of such trades,making it a crucial hub for hedging risks.

Clearinghouses stand between the two sides of a derivative wagerand hold collateral, known as margin, from both in case onedefaults. At issue is a so-called equivalence decision that the EU adopted latelast year, which allows EU firms to use derivatives clearinghousesin the U.K. on a temporary basis even in the event of a no-dealBrexit. A sudden loss of access to this critical pillar of themarket could pose financial stability risks, officials in Brusselssaid at the time.

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