Ending months of speculation over her White House bid, former Alaska governor Sarah Palin Thursday announced that she would not be seeking the Republican presidential ticket in 2012, saying "my family comes first."
"After much prayer and serious consideration, I have decided that I will not be seeking the 2012 GOP nomination for President of the United States," Palin said in a letter posted on her website.
"My family comes first and obviously Todd (her husband) and I put great consideration into family life before making this decision," she wrote to her supporters.
Palin's announcement ends months of uncertainty over the 47-year-old photogenic Republican leader's political plans.
Palin had fanned speculation that she was considering a bid for the presidency when she announced a summer bus tour with stops in early-voting US states.
Her announcement comes a day after New Jersey Governor Chris Christie ruled himself out of the race.
Ex-Massachusetts Governor Mitt Romney and Texas Governor Rick Perry lead the Republican pack to challenge Barack Obama for the White House in 2012.
But she made it clear that in the coming weeks she would "co-ordinate strategies to assist in replacing the president, re-taking the Senate, and maintaining the House".
"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 nation's governors to congressional seats and the presidency," she said.
Palin told her supporters that she could help the Republican cause more by working to elect others.
"In the coming weeks I will help coordinate strategies to assist in replacing the president, re-taking the Senate, and maintaining the House."
Palin did not endorse any of the existing presidential contenders, but ruled out running as a third-party candidate.
Palin burst on to the national political scene in 2008 as the vice-presidential candidate on the White House ticket of Senator John McCain.
After losing the 2008 election she returned to Alaska, and then stepped down as governor half way through her first term. However, she has been a champion of the conservative Tea Party movement and is one of the most recognisable faces in US politics.
Meanwhile, Rick Perry said he respects Palin's decision.
"Sarah Palin is a good friend, a great American and a true patriot. I respect her decision and know she will continue to be a strong voice for conservative values and needed change in Washington," he said.
