McLaren Formula 1 boss Andreas Seidl insists that the team's outgoing driver Carlos Sainz Jr should not be allowed to drive for Ferrari in the Abu Dhabi young driver test.
The FIA has given permission for drivers who haven't raced in 2020 to join what was originally slated as a test for drivers who have completed no more than two grands prix, thus opening the door for Fernando Alonso to drive a contemporary Renault for the first time since a 100km filming day in October.
Sebastien Buemi is also expected to participate for Red Bull, while Robert Kubica will reprise his third driver duties with Alfa Romeo.
Ferrari was one of several teams left frustrated by the decision to let Alonso gain more knowledge of Renault's 2020 car, and the Maranello team has now been lobbying for Sainz to be allowed to take part.
The Spaniard said on Thursday that he will be contractually free of McLaren commitments, and he is keen to do the test.
If the FIA does grant permission, he would take the place of regular Ferrari sim driver Antonio Fuoco, who is currently scheduled to drive one of the Italian team's two cars.
Along with Racing Point, McLaren decided to skip the test to save money and because it didn't have a young driver who needed mileage, believing there was never any option to run incoming driver Daniel Ricciardo.
Seidl remains adamant that Sainz is not eligible to take part.
"The regulations are clear, so I don't see any way that Carlos is driving the car," he said.
"For us, it's clear that based on the regulations that exist we can't run there with an active F1 driver, and that is why we made the decision together with all the other teams already in April that we don't take part in this test.
"And at the moment, I think that is still valid. From our point of view, there's no plan to do this test."
Pressed on Ferrari's ongoing attempt to get permission he said: "There is no room for him to drive a Ferrari because, unfortunately for him, the rules do not allow [it]. It's a young driver test.
"I only know what the rules are saying. And if someone else decided different, there's nothing I can do against it."
Even if the test was suddenly opened up to all drivers, McLaren could not take part because transport of its equipment and personnel has already been arranged.
Seidl added that there is no need to seek any kind of clarification for the future from the FIA because this year's testing arrangements are a one-off, a result of cost-saving efforts earlier in the year when the pandemic first hit.
"That was a unique situation for this year," he said.
"I think for now the regulations for next year are clear again, and more back to normal."