The two companies had previously set July 18 as the cutoff point to finalise the US$75 billion deal for Microsoft to acquire Activision, which now gets pushed by three months to Oct 18.

In return, Microsoft agreed to pay Activision an increased break-up fee in case either side walks away from the deal that could reach as high as US$4.5 billion, a filing showed.

Both sides said they remained firmly committed to the deal and were emboldened by a major victory in a US court which rejected an attempt by the Federal Trade Commission to squash the sale.

“The recent decision in the US and approvals in 40 countries all validate that the deal is good for competition, players, and the future of gaming,” tweeted Lulu Cheng Meservey, Activision Blizzard’s head of corporate affairs.

Microsoft president Brad Smith said the extension gave “ample time” to close the sale and that he was “confident about our prospects for getting this deal across the finish line”.

The acquisition of Activision by Microsoft will create the world’s third biggest video gaming giant and has faced significant scrutiny by antitrust regulators.

The companies made substantial commitments to regulators in the European Union and other antitrust authorities in order to win their approval.

These answered concerns that Microsoft would bar their rivals access to some of Activision’s most popular games, including Call of Duty, one of the world’s most popular gaming titles.

In April, the UK rejected the deal over its threat to the still developing cloud gaming sector, but agreed to take another look after the FTC’s defeat in a US court.