Red Bull won't let Ricciardo test 2018 Renault

The test is the only opportunity for drivers who are changing camps to gain on-track experience with their new teams before proper 2019 testing kicks off in February.

For those drivers making 'friendly' moves, such as Charles Leclerc to Ferrari, Pierre Gasly to Red Bull and George Russell to Williams, testing for their new teams is a no-brainer.

However, Red Bull has turned down Renault's request to make Ricciardo available.

"I'm not allowed to test," the Australian said in Austin. "I can't drive for Red Bull and they won't let me drive for Renault.

"So it is okay. I can have a holiday."

Red Bull Racing team principal Christian Horner said that it was a question of Ricciardo fulfilling his contractual obligations.

"He's under contract past that date, so he won't be doing the test," Horner told Motorsport.com.

"There was a question, 'Is he available?' It's very clear that he's not, so it's very simple. They just asked what his availability was, and he's not available.

"He's still got obligations to tidy up until the end of his contract."

Sauber is still hoping that Ferrari will give Kimi Raikkonen permission to do the Abu Dhabi test with the Swiss outfit.

"We will have to discuss the point," team principal Fred Vasseur told Motorsport.com. "It makes sense for us, I think it make sense for everybody.

"For every single team it makes sense to have the feedback from the next driver. We will discuss, we are not in a rush. We can discuss in Abu Dhabi!"

Antonio Giovinazzi will drive for Sauber in the single-team Pirelli test that follows the Mexican GP.