Andrea Dovizioso will take a sabbatical in 2021 but hopes to return to the MotoGP™ grid in future.
It was confirmed in August that Dovizioso's eight-year partnership with Ducati would come to an end at the conclusion of this season.
The 34-year-old, who has 15 wins and 62 podiums to his name in the premier class, had been linked with a test rider role next year.
However, Dovizioso has opted to bide his time and wait for a better opportunity to come up.
He said in a statement: "Over the last few months, I have received several offers to work as a test rider in developing MotoGP™ projects and I am grateful for the consideration received by the manufacturers. However, I have decided not to make any commitments and to remain free from formal agreements for now.
"I have an immense passion for racing. I still have the ambition to compete and fight to win. I will return to MotoGP™ as soon as I find a project driven by the same passion and ambition that I have and within an organisation that shares my same objectives, values and working methods.
"Now I am focused on finishing the world championship in the best possible way, and I have already started developing some projects with my partners."
Ducati confirmed in September that Francesco Bagnaia would partner Jack Miller at the factory team in 2021.
Dovizioso finished second in the riders' standings in each of the previous three campaigns and looked set to be a serious title challenger after Marc Marquez was ruled out for the majority of the 2020 season through injury.
However, he slid from first in the standings to fourth after crashing out on lap one of the Catalan Grand Prix and now sits 45 points behind championship leader Joan Mir.