T-Mobile U.S. Inc. is set to win U.S. antitrust approval for its takeover of Sprint Corp. on Friday, according to a person familiar with the matter, moving the wireless carriers a step closer to completing a deal that has been more than a year in the making.

The Justice Department's antitrust division is scheduled to announce a settlement that will require the companies to sell assets to Dish Network Corp. to preserve competition in the industry, said the person, who asked not to be named because the review is confidential.

Under the settlement, Dish will pay about $5 billion for wireless assets, including the prepaid mobile businesses and spectrum. The arrangement is intended to resolve competition problems stemming from uniting the No. 3 and No. 4 wireless carriers.