The lucrative activity of euro clearing remains one of the main battlegrounds between London and Brussels in Brexit talks.

Back in June, the European Commission proposed to give broad powers to itself, the European Central Bank and the European Securities and Markets Authority allowing them to force foreign clearing houses deemed “substantially systemically important” to move into the bloc, or face exclusion from the EU market.

Now the European Parliament is reportedly aiming to soften plans to give EU regulators the power to force London’s main clearing house to relocate.

“We don’t want to give those bodies this right to use total discretion in deciding what is cleared where,” Danuta Hubner, chair of the powerful constitutional affairs committee of the EU legislature, told the Reuters news agency.

Hubner, who is the leading EU lawmaker on clearing, also said her report on the Commission’s plan, due to be finalised by month’s end, will include stricter conditions for regulators to determine whether clearing should be moved.

As reported by Reuters, she said she was confident parliament would back her amendments, although other prominent lawmakers have previously called for a sweeping relocation of euro business from London to the EU after Brexit.

Any new rules would also need approval from EU member states, which are competing to attract business from London, Europe’s biggest financial centre, after Brexit.

If confirmed by parliament, Hubner’s unexpected move is likely to be welcomed by the financial industry, which has warned that forced relocation could split markets, increase trading costs and diminish the status of the euro – besides threatening thousands of jobs in the City of London.

At the moment, most derivatives denominated in euros are cleared in London through LCH, a subsidiary of the London Stock Exchange (LSE.L) which reported record volumes last year across multiple clearing services.

As noted by Reuters, LCH is the only clearing house operating in the EU that, once turned into a foreign company by Brexit, could be deemed substantially systemically important by EU regulators, Hubner said. Its German rival Eurex is a comparable size, but the new rules would not apply to it because it is in the EU.

LCH is currently one of 17 clearing houses authorized in the European Union. Another 28 foreign central counterparties in countries such as Hong Kong, Singapore, Switzerland and United States, are also allowed to operate in the EU.

Under the law proposed by the Commission, non-EU counterparties operating in the single market under a so-called equivalence regime and deemed “systemic” would be subject to stricter supervision.

The EU allows non-members to operate in the bloc if Brussels deems that the other country’s legal and regulatory regime is at least as good, or equivalent, as its own.

Those counterparties classified as “substantially systemically important”, however, could face relocation so they can be overseen more closely by the bloc’s supervisors.