Lewis Hamilton told his future Ferrari boss, Frederic Vasseur, that he didn’t want to make his debut in a red cockpit in the post-Abu Dhabi GP test.
While the man he is replacing, Carlos Sainz, will be in action for his new team - Williams - after the season finale, Hamilton will be busy elsewhere.
"I don’t want to block him," Vasseur said, referring to Sainz.
As for why Hamilton is not being released by Mercedes boss Toto Wolff, the Frenchman added: "You will have to ask Toto.
"They have a contract so I didn’t even ask Toto."
Wolff confirmed the story: "Fred didn’t ask. I think it maybe makes a difference if you’re going to Williams, but we have contractual agreements with sponsors."
Wolff said Hamilton, 39, is embarking on a post-season "farewell" after so many years with Mercedes, with "lots of activities" already planned.
"Lewis and I spoke about it briefly and he said ’I guess that (the Abu Dhabi test) is not going to work. And I said ’Yeah, I don’t think it’s going to work.’"
When asked for his version in the Qatar paddock, Hamilton admitted that he will "absolutely" be slightly disadvantaged by not testing the 2024 Ferrari after Abu Dhabi.
"It will definitely slow down the process and make the start of next year more difficult, but we will do everything we can to make up for it," said the seven time world champion.
"I know that Fred wanted me to do the test, but I was in two minds. The idea of getting behind the wheel of a red car for the first time in Abu Dhabi did not excite me too much. In an ideal world, I would like the first runs to be done without much scrutiny.
"Toto and the team had planned ahead for me to meet some sponsors and say goodbye to them, so I don’t think I would have been allowed to take part in the tests even if I had asked," Hamilton insisted.
"I have a contract with Mercedes until December 31 and it is not a problem for me because I told Fred in advance that I didn’t really want to do it."