In a post-interview comment, caught on camera and aired on the Internet, Fleming called Richardson an "idiot" for his pre-match comments on Sunday's fourth day of the first Test against West Indies.
Fleming also called Richardson "one of the most boring players to watch, and from what I've seen so far in your commentary, it is crap".
But both Fleming and Sky Television on Monday quelled any suggestions the pair had fallen out with each other.
Fleming said the skit was done for a cricket show fronted by Richardson, and he was asked by the former Test opener to "slag him off".
Speaking after New Zealand pulled off a 27-run win over West Indies here Monday, Fleming laughed when asked about the clip and said he was surprised the joke had received publicity.
"I was asked by Mark, who I get on very well with, to do a piece for Cricket Company. He said he was going to give me the opportunity to slag him off at the end. I said, 'yeah, I'll take a piece of that.'
"It's pretty humorous that it's made it this far. Seriously, it was just purely to entertain Mark. It must have been pretty convincing."
Sky Television's producer of cricket and former New Zealand captain Martin Crowe released a statement saying the interview was a spoof.
"It was scripted and not real although it has appeared on the Internet as a news item," Crowe said.
Richardson, who retired from Test cricket more than a year ago, was well known as a joker within the New Zealand camp.