Sarah Palin has ruled out running for US president in 2012.
The former Republican vice presidential candidate made the announcement in a letter to supporters on Wednesday.
Palin said she based her decision on "a review of what common sense conservatives and independents have accomplished, especially over the last year''.
"I believe that at this time I can be more effective in a decisive role to help elect other true public servants to office from the nations governors to Congressional seats and the Presidency,'' Palin said in the letter published on the American ABC News website.
Palin said family and religious life were major factors in her decision.