Britain’s antitrust watchdog said that a new merger investigation into Microsoft Corp.’s $69 billion Activision Blizzard Inc. deal may be needed if the duo restructure their deal in a bid to reverse a UK veto.

The CMA said Tuesday it had applied to put the appeal trial against its decision to block the deal on hold after a US court ruled that the companies could move forward with the deal. That gives the firms a chance to come up with potential new remedies to allay the UK concerns.

“Merging parties don’t have the opportunity to put forward new remedies once a final report has been issued, they can choose to restructure a deal, which can lead to a new merger investigation,” a spokesperson from the Competition and Markets Authority said in a statement Wednesday.

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“Microsoft and Activision have indicated that they are considering how the transaction might be modified, and the CMA is prepared to engage with them on this basis,” the spokesperson said. “These discussions remain at an early stage and the nature and timing of next steps will be determined in due course.”