Republican vice presidential nominee Sarah Palin speaks during a rally in Ohio, 29 Sep 2008

Alaska Governor and former Republican vice presidential candidate Sarah Palin says she will resign from office later this month and will not seek re-election.

Palin spoke Friday at a press conference outside her home in the small town of Wasilla, Alaska. Her surprise announcement raised speculation that she would seek to be the Republican Party's presidential candidate in 2012.

Palin -- who is seen by many as a rising star in the party -- was U.S. Senator John McCain's running mate in the 2008 US presidential election which they lost to President Barack Obama.

Palin said she would rather make "positive change outside government at this moment in time." But the outgoing governor did not announce any specific plans.

She said she would formally step down and transfer authority to Alaska Lieutenant Governor Sean Parnell on July 26.

Palin indicated Friday that she has grown frustrated with some aspects of governing. She complained of the ridicule her family has faced, but also spoke of her efforts to clean up government corruption and "aggressively" develop Alaska's energy resources.

Sarah Palin is the second woman to be nominated for vice president on a major-party ticket and the first for the Republicans. She was elected governor of Alaska in 2006 after one term as mayor of Wasilla. She was the state's youngest and first woman governor.