The U.K.'s Competition and Markets Authority said Tuesday that Vodafone and Three's £15 billion ($19.5 billion) merger will likely be approved if the two firms proceed with billions of pounds of infrastructure investment and add customer protections.

The $19 billion merger between Vodafone and Hutchison's Three UK is likely to be given the regulatory green light as Britain's need for investment outweighs short-term competition concerns.Britain's anti-trust regulator said on Tuesday it believed the combination of the country's third and fourth biggest mobile operators could be "pro-competitive" if certain measures and remedies are implemented.

Vodafone’s deal to merge its U.K. business with rival operator Three could proceed if competition concerns are addressed, the country’s antitrust authority said.

The merger between Vodafone and Hutchison's Three UK is likely to be given the go ahead as investment commitments overcome concerns over competition, a British regulator said in a provisional ruling on Tuesday.