"Given the scope and complexity of our business, our Government Affairs team works with a number of political consulting firms to help navigate the numerous federal government and regulatory matters that are relevant to us. This list of agencies, which is publicly available, includes Turnberry Solutions which we hired last August," a T-Mobile spokesperson said.

In a statement to NBC News, the telecommunications company said it hired Turnberry Solutions in August for its perspective "on a variety of topics, including the pending transaction." It retained the lobbying firm as part of an effort to secure federal approval for its merger with Sprint, The Wall Street Journal reported Friday .

T-Mobile hired a lobbying firm tied to former Trump campaign manager Corey Lewandowski, the telecommunications company said Friday.

"Corey Lewandowski is now affiliated with that firm and they have offered perspective to T-Mobile on a variety of topics, including the pending transaction."

Lewandowski is getting paid as part of T-Mobile's contract with Turnberry, according to documents reviewed by the Journal, as well as people familiar with his involvement. The newspaper said Lewandowski's specific role is unclear.

Data from the Senate Office of Public Records shows Deutsche Telekom, of which T-Mobile is a subsidiary, has paid Turnberry Solutions $70,000 so far in 2018, according to the Center for Responsive Politics' OpenSecrets database. Deutsche Telekom paid the lobbying firm $30,000 in 2017, OpenSecrets' records show.

Lewandowski worked for the Trump campaign until June 2016. He drew headlines after he was seen on video grabbing a reporter approaching then-candidate Donald Trump at a rally in March 2016, for which he subsequently received a misdemeanor battery charge. That charge was later dropped.

In a September report from Politico, Lewandowski said he has "nothing to do with Turnberry Solutions." Politico also reported T-Mobile's partnership with Turnberry in January.

T-Mobile and Turnberry Solutions did not immediately respond to CNBC's requests for comment on the Journal's report. A Sprint spokesman referred CNBC's request to T-Mobile.