The UK’s Competition and Markets Authority (CMA) has approved the $570 million acquisition of CWT by American Express Global Business Travel (Amex GBT). A statement from the authority said “the group has concluded that CWT is a significantly weaker competitor than in the past and is likely to continue to weaken in the future and that there are other suppliers who will offer customers an alternative to the merged business.”

It continued: “The group is therefore satisfied that the merger is not expected to result in a substantial lessening of competition in the global market for the supply of business travel agency services and has cleared the deal.”

In a summary of its final report released on Thursday, the CMA cited CWT’s “continuing financial difficulties” and said that “its financial position is unlikely to improve and it potentially faces a trajectory of continuing to lose more business than it will gain.”

The CMA said its bidding analysis had confirmed that BCD Travel and Amex GBT are the two strongest competitors in the market by far, and both are substantially stronger than CWT. In addition to “strong competition” from BCD, CMA said Amex GBT currently faces “a material competitive constraint from FCM and faces an increasing constraint from CTM and Navan as they continue to grow.”

Amex GBT CEO Paul Abbott said: “We are pleased with the CMA decision. By combining with CWT, we can provide even more value and choice to customers and suppliers and more opportunities for CWT employees.”

Eric J. Bock, Amex GBT’s chief legal officer and global head of M&A, said the CMA decision “also further reinforces our belief that the lawsuit initiated by the U.S. Department of Justice (DOJ) is fundamentally flawed, taking a narrow and outdated view of competition, and disregarding the emergence of numerous significant competitors in business travel.” He added: “We stand by the benefits of combining with CWT and are confident in the merits of our legal position. We are prepared to prove this in court if required.”

In January, the U.S. Department of Justice filed a lawsuit to block the merger of the two TMCs, with a trial scheduled for September.