FIA presidential candidate Ari Vatanen was not granted a pass to walk on the grid prior to Sunday's Italian Grand Prix.
Britain's Guardian newspaper quoted Sir Jackie Stewart, who is barracking for the Finn and former European parliamentarian to defeat Jean Todt in October's elections, as describing the snub to the potential next FIA president as "shocking".
Grid passes, like Vatanen's paddock pass, are controlled by F1 chief executive Bernie Ecclestone, who defended the decision not to grant one to Vatanen.
It is unthinkable that Todt, the former Ferrari team boss and Max Mosley's preferred successor, would be similarly not allowed on the grid.
Ecclestone said: "I don't see any reason for him (Vatanen) to be on the starting grid. He's not a sponsor, he's not a team owner."
The 78-year-old also suggested that the demand for passes at historic Monza is particularly high.
"This is what happens, particularly at Monza. There were 10 million politicians and their mothers who wanted to be on the grid -- goodness only knows why, but they did.
"We have a limited number of passes which we had agreed to allocate. That was it," the Briton added.