The Federal Trade Commission’s timeline for deciding whether to allow Staples Inc.’s takeover of Office Depot Inc. is likely to be delayed, according to people familiar with the matter.

The companies and FTC antitrust enforcers had previously entered into a timing agreement that could have required the commission to make decision by early next week. But the regulatory landscape changed when antitrust officials at the European Commission announced Sept. 25 that they had opened their own investigation of the acquisition.

European officials, who cited preliminary concerns about how the merger would affect business customers, said they have until February to make a decision on whether to allow the deal.

With the addition of extra months of review across the Atlantic, the companies and the FTC have been in discussions about extending the timeline in the U.S., people familiar with the matter said.

It couldn’t immediately be learned how far the U.S. timeline might extend. It is also not clear which side might benefit from any extra time. It could give the FTC more room to try to build a case if it chooses to challenge the deal. But a time extension also could give the companies more opportunities to try to address any FTC concerns.