(Reuters) -Britain on Thursday referred Facebook Inc’s acquisition of GIF website Giphy for an in-depth probe after Facebook told the country’s competition watchdog it would not be offering any concessions to address antitrust concerns. The Competition and Markets Authority (CMA) last week gave Facebook and Giphy five working days to offer proposals to address its concerns over their merger deal. However, the CMA said on Thursday that Facebook had informed it last Thursday that it would not be offering any remedies to address its competition concerns.] “We will continue to fully cooperate with the CMA’s investigation,” a Facebook spokesman said in an emailed statement. “This merger is good for competition and in the interests of everyone in the UK who uses GIPHY and our services - from developers to service providers to content creators,” he added. Giphy did not immediately respond to a request for comment. Facebook, the world’s largest social media company bought Giphy, a website for making and sharing animated images, or GIFs, in May last year to integrate it with its photo-sharing app, Instagram. However, a source told Reuters in June that Facebook was pausing the integration. The CMA began an initial investigation in January at a time when the social media network was under global regulatory scrutiny over antitrust concerns. After the initial investigation, the CMA said that if the two companies remain merged, Giphy could have less incentive to expand its digital advertising, raising concerns about Facebook’s existing market power in display advertising. Facebook had said that Giphy’s integrations with other social platforms like Twitter Snapchat and ByteDance’s TikTok would not change.