Speaking to Reuters on Tuesday after a rehearsal for the show, Williams said he will be performing "a medley, a smorgasbord of my greatest hits" alongside Russian soprano Aida Garifullina.
"I would love to do 'Party Like A Russian.' Unfortunately I've been asked not to do 'Party Like A Russian," he said.
Williams immediately added: "Actually, it has nothing to do with not being asked. It's about me doing my biggest hits that are the best known."
In the 2016 track, the Briton sings "it takes a certain kind of man with a certain reputation, to alleviate the cash from a whole entire nation." In the accompanying music video, ballerinas twirl around Williams in a lavish setting.
Pro-Kremlin media outlets were critical, suggesting Williams could be snubbed by Russian event organisers because of the song.
In response, Williams wrote on Twitter at the time that "this song is definitely not about Mr Putin."
"'Party Like A Russian'" was a big hit for me, it was like my biggest hit here in Russia, so I'm really pleased," Williams said.
"I didn't mean any disrespect by it at all. It's more of a Monty Python-esque kind of humour. I'm not mocking anybody. It's just a pop record."
Williams, who has previously performed at private parties organised by wealthy Russian business people, said he loved coming to Russia.
"Because when we grew up, Russia might as well have been on a different planet," he said. "And then peering behind the Iron Curtain as it was, as it is, you get to meet the people, you get to experience the culture and you realise that, you know, they are just humans, just like me and you."
Williams said performing at the opening ceremony of the World Cup was an honour.
"Something like this happens, and you pinch yourself," he said. "I'm pinching myself again... And I just don't want to get too overwhelmed because I know how big the stage is."
The performance will take place half an hour before Russia face Saudi Arabia in the tournament's opening match at Moscow's Luzhniki stadium.
(Reporting by Gabrielle Tétrault-Farber; Editing by Christian Radnedge)
