The U.K.'s Competition and Markets Authority announced it is investigating American Express Global Business Travel's proposed acquisition of rival travel management company CWT.
Amex GBT's $570 million deal to purchase CWT was announced in March and would bring together the largest and third-largest TMCs in Europe. But the transaction will have to receive regulatory approval in key markets such as the U.S., U.K. and the European Union
The CMA said in a statement that it was considering whether the blockbuster TMC deal would fall "under the merger provisions of the Enterprise Act 2002" as part of its preliminary Phase 1 investigation.
"And, if so, whether the creation of that situation may be expected to result in a substantial lessening of competition within any market or markets in the United Kingdom for goods or services," added the CMA.
The authority is inviting comments on the impact of the Amex GBT-CWT deal "from any interested party", with a deadline for submissions of June 18.
The CMA has also set the deadline of July 30 to decide whether to give the acquisition the green light or go ahead with a more in-depth Phase 2 investigation.
Amex GBT has said that it hoped to complete the purchase of CWT during the second half of this year.