President Trump's national security adviser has denied knowing the editor of The Atlantic after accidentally adding him to a sensitive group chat.

Journalist Jeffrey Goldberg is accusing Mike Waltz of lying about talking with him — ridiculing on Sunday the claim that his phone number was mysteriously “sucked into” the national security adviser’s cellphone before being included in a Signal group chat about Yemen airstrikes.

Mr. Goldberg, who was included on a private text thread discussing war plans, was a longtime national security reporter who became editor of The Atlantic in 2016.