Sergey Sirotkin says he left Williams at the end of last year following a "mutual decision".
The once-great British team was already struggling in 2018, when Russian Sirotkin was the race driver.
But a few days ago, the 23-year-old - now Renault's reserve driver and set to help develop Pirelli's 18-inch tyres for 2021 - admitted he would be happy to replace the struggling Robert Kubica.
"It is worth noting that no one tried to get rid of me," Sirotkin told Russia's government-run RT broadcaster.
"A mutual decision was made," he said.
It is believed Sirotkin is referring to his backer, SMP Racing, which is the motor racing arm of the Russian bank SMP Bank.
"Evaluating the big picture, we understood what mistakes were being made and which direction we were going in," he said.
"Therefore, for the project as a whole, it was the best solution."
But Sirotkin says that from a personal perspective, he would be happy to return to Williams.
"I am an athlete and I want to get competitive practice with the best drivers in the world, even with the slowest car," he insisted.
