Atalla, who has used a wheelchair since suffering from polio as a child, helped Gervais create the hit U.K. version of the work-based comedy, but hit out at the star for repeatedly making jokes at disabled people's expense - including mocking his own disability when accepting a prize together for "The Office" at the British Comedy Awards in 2001.
According to British newspaper The Times, he said at the Edinburgh International Television Festival in Scotland: "I was complicit in him making fun of the wheelchair. But I don't really look back at it with an enormous amount of pride. I feel a little bit uncomfortable about some of the stuff we did together."
The producer said that he often made jokes himself to make people comfortable around his disability, but explained that Gervais' work since, including TV series "Derek" about a man with learning difficulties, has made him reconsider whether indulging the comedian was a good idea.
"But the question I get asked quite a lot about it is when Ricky was doing it there was another level of awkwardness to it," he added. "I was the producer of the show so I was not unpowerful in that dynamic, but he did then go on to make quite a few shows about disability so maybe he is obsessed with it."
Gervais has frequently defended his more offensive material, telling GQ he could "justify every joke I've ever done."