Mark Webber said in comments published on Thursday that had no intention of staying in Formula One next season and did not decide to leave as a result of the team orders controversy.
Options to remain in F1 were on the table, he added, but he said he had already decided to stick to his own plans to find a new challenge for 2014.
Asked in an interview on his official website, markwebber.com, if he had received offers to stay, he said: "Yes. But since Formula One as a category wasn't on my radar for 2014, they weren't a consideration for me."
Webber, 36, announced earlier that he was joining Porsche's new sportscar programme at the end of the F1 season.
His Red Bull team had intended to speak to him about his future in the coming weeks and other outfits were interested in recruiting him for next season, he added.
But Webber said he was determined to ignore them: "I've had a personal plan and I've stuck to it. This is the next chapter.
"I never asked the team for more work but I've remained in touch with (Red Bull owner) Dietrich Mateschitz over the last six to eight months and he's been absolute quality for me.
"Going forward I will remain tightly inside the Red Bull family, working with the brand, and watching and supporting fellow Red Bull athletes push the boundaries."
Webber also said that a return to F1 in the future was "extremely unlikely", particularly given new engine rules scheduled to come into effect in 2014.
The announcement came before most teams had arrived at Silverstone for this weekend's British Grand Prix.
Normally, F1 teams are prepared for every eventuality, particularly about driver line-ups.
But Webber stole a march on Red Bull, with the outfit saying an announcement on his replacement would be made later in the season.