“Why is it,” Mr. Warner asked, the American prosecutors “believe that they have a right to the World Cup?”

As dramatic background music swelled, he went on, holding up The Onion article again, to accuse the United States of hypocrisy for accepting the right to host the (entirely fictional) “Summer World Cup, 2015, from the very same organization that they are accusing of being corrupt. That has to be double standards.”

In the video, Mr. Warner also said he was “consoled by the fact that many of you on the blogs, on Twitter, on Facebook, on other channels, throughout were very supportive of me and still are.” He assured his supporters that, “At the end of the day, all of the allegations against me shall be proven to be unfounded.”

“You see, it is not when you’re up that you know who your friends are,” he said, “it’s when you are perceived to be down.”

After Mr. Warner’s error in mistaking The Onion for a news source was mocked on social networks, the video disappeared without explanation from his website and social media accounts.

Two hours later, it was replaced by an edited version, missing 63 seconds and all references to The Onion.

Mr. Warner is far from the first person to mistake The Onion for a genuine news source. In 2012, an Iranian news agency backed by hard-liners reprinted an Onion poll that found rural voters in West Virginia preferred Mahmoud Ahmadinejad to President Obama.