“We must protect the creative talent throughout the Time Warner business,” the chief of AT&T vowed in the wake of the merger announcement. (Kena Betancur/AFP/Getty Images)

The chief executive of AT&T has pledged to maintain the journalistic independence of CNN if his company’s $85 billion purchase of CNN’s parent company, Time Warner, is completed.

In an email to a former AT&T executive, AT&T chief Randall Stephenson on Sunday called the cable news network “culturally significant” and said it would remain “independent” if AT&T owns it.

“CNN is an American symbol of independent journalism and First Amendment free speech,” wrote Stephenson, a day after his company’s megadeal was announced. “We must protect the creative talent throughout the Time Warner business. The talent must fundamentally believe they will be afforded the same creative license [after the merger] they have today.

“This is particularly important as it applies to an institution as culturally significant as CNN. My board and I are not confused. Ensuring the public that CNN remains independent from an editorial perspective is critical.”

Republican presidential nominee Donald Trump has attacked CNN and some of its journalists for months, branding it “the Clinton News Network” because of its alleged favoritism toward his opponent, Hillary Clinton. He blasted the proposed merger Saturday as “too much concentration of power in the hands of too few” and said that, if elected president, he would try to block such consolidations.

Stephenson’s email does not mention Trump, though. It was written to former AT&T executive Jim Cicconi — who retired last month as the company’s top Washington policy executive — in response to concerns first raised Saturday by Tom Johnson, CNN’s former president. Johnson wrote that ensuring CNN’s independence was the “most important” issue in the merger.

Cicconi forwarded Stephenson’s comments, with his permission, to a long list of media executives and journalists that Johnson had sent his original email to, including former NBC anchor Tom Brokaw, CNN founder Ted Turner, CNN correspondent Christiane Amanpour, Washington Post editor Martin Baron, New York Times Co. Chairman Arthur Sulzberger Jr. and Politico publisher Robert Allbritton.

CNN Worldwide — which includes the flagship domestic network, CNN International and the HLN cable network — is a small but important part of the proposed combination of the two companies.

AT&T is a leading “content” transmitter through its DirecTV satellite service, cable and wireless telecom businesses, and Time Warner is a leading producer of some of that content. In addition to CNN, Time Warner owns HBO, Warner Bros., TBS, Cartoon Network and other cable networks.

CNN would give AT&T its first major foothold in the news business, and it is a powerful platform not just for transmitting news but also political opinions as well. CNN’s own journalists would surely object if a new owner tried to influence CNN’s programming to favor its own interests.

The proposed buyout will almost certainly undergo many months of regulatory review in Washington before it can be finalized. AT&T will probably have to assure officials at the Justice Department and Federal Communications Commission that it does not intend to interfere with CNN to gain approval for the deal.

Comcast made multiple concessions to win the government’s permission to buy NBC Universal in 2011, including making a formal pledge to uphold “journalistic independence” at all of NBC’s networks and TV stations. NBC owns NBC News, MSNBC, CNBC, Telemundo and a group of TV stations, including WRC-TV in Washington, that produce local newscasts. Comcast also committed to maintaining an ombudsman at NBC News “to address any issues that arise.”

Time Warner subsequently hired Jeff Zucker, the former president and chief executive of NBC Universal, in late 2012 to run CNN Worldwide.

Johnson, the former CNN president, said in a brief interview Sunday that he had “no reason” to think AT&T would weaken CNN. “From all I have learned about Randall Stephenson in the past two days, I predict that he will be a strong champion of high-quality news standards,” said Johnson, who ran CNN from 1990 until his retirement in 2001.