The European Union’s decision to approve Microsoft Corp.’s $69 billion plan to buy Activision Blizzard Inc. while the U.K. blocked the takeover raises “important questions,” according to Margrethe Vestager, the EU’s competition chief.

While regulators cooperate, she said they sometimes have disagreements — such as last week when the EU waved through the deal with commitments aimed at bolstering the nascent market for cloud-based gaming that were rejected out of hand by the UK’s Competition and Markets Authority.

“Divergence of course raises really important questions regarding our assessments, our remedy policy, our cooperation,” she said at a Brussels conference.

“Where we diverged with the CMA was on remedies,” she said. “We accepted a 10-year free license to consumers to allow them to stream all Activision games for which they have a license via any cloud service. And why did we do this instead of blocking the merger? Well, to us, this solution fully addressed our concerns. And on top of that, it had significant pro-competitive effects.”

While the EU’s approval was a boost to the deal, its prospects now hinge on legal challenges in the UK and US. Microsoft lodged a suit at the UK’s Competition Appeal Tribunal on Wednesday. Meanwhile, it’s yet to face the US Federal Trade Commission on the deal after the agency sued to block it. A trial isn’t set to begin until early August and isn’t likely to produce a decision until the end of the year.

Read More: Microsoft Appeals UK Decision to Block Activision Mega Deal

--With assistance from Stephanie Bodoni.