Brexit: Europe's new finance rules put 83,000 U.K. jobs at risk

The European Union is preparing to steal one of Britain's crown jewels.

The bloc proposed rules on Tuesday that would give it the power to force a large slice of London's financial services to move out of the city after Brexit, putting at risk an estimated 83,000 jobs.

Despite not using the euro itself, the U.K. acts as the primary go-between for buyers and sellers of financial products priced in euros that play a vital role in Europe's economy.

Known as euro clearing, it's a massive business involving transactions worth $1.5 trillion each day. Rival financial centers such as Paris and Frankfurt have coveted the lucrative activity for decades but have failed so far to loosen London's grip.

The European Central Bank has long argued that the clearing of such vast quantities of trades should take place inside the group of 19 countries that use the currency. The bank says it needs to monitor what's happening to ensure the financial stability of the eurozone.

As long as Britain remained in the EU, the central bank wasn't able to force London to drop the business. But now Britain is set to ditch the EU, all bets are off.

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The proposal from the European Commission says that allowing the clearing houses to be based outside the EU could pose a risk to the continent's financial system.

It recommends that regulators have the power to require "a limited number" of systemically important clearing houses to be based in the EU.

"The foreseen withdrawal of the United Kingdom from the EU will have a significant impact on the regulation and supervision of clearing in Europe," the Commission acknowledged.

The rules still need to be debated and approved by EU states and members of the European parliament.

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The damage to London could stem from the jobs that would disappear if clearing operations are forced to move.

While the number of people employed directly by the four clearing houses that handle the majority of transactions only numbers in the hundreds, the supporting infrastructure is massive.

The London Stock Exchange owns the biggest clearing house. It commissioned a report last year that found up to 83,000 British jobs could be lost over seven years if the activity moves out of London and into the eurozone.

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The London Stock Exchange did not immediately respond to a request for comment.

The U.K. is lobbying hard to keep the clearing operations in London. Its main argument is that moving the hub could cause havoc.

TheCityUK, a lobby group, has warned the move would cause uncertainty, higher costs of doing business and fragmentation in the market.