Mrs Arroyo has been in power since 2001
Philippine President Gloria Arroyo has announced she will run for a seat in Congress in next year's elections.
She said she wanted to continue to work in public service and represent her home province of Pampanga.
Mrs Arroyo must step down as president when her term expires after elections in May.
The opposition has criticised her decision as a bid to hang on to power and retain immunity from potential corruption charges.
"After much contemplation I realised I am not ready to step down completely from public service," Mrs Arroyo said in a radio interview.
"As you all know, the people from my congressional district in Pampanga asked me to stay in politics."
A seat in the lower house of the Congress could also potentially give her a platform to change the constitution so she could continue running the country as prime minister.
Her Lakas-Kampi CMD coalition would have to gain enough seats in both houses of Congress in May's elections for this to be possible.
Mrs Arroyo dismissed the scenario in the interview, calling it "hypothetical".
She also said a congressional seat would not protect her from corruption charges.
Opponents have said her position as president would give her an unfair advantage in campaigning for election.
Mrs Arroyo has fended off four impeachment motions in Congress since 2005 and her opponents have said they plan to file corruption charges against her when her presidential immunity ends.
Her successor as head of the Lakas-Kampi CMD coalition is former defence secretary Gilberto Teodoro but he is trailing in opinion polls.
The current favourite is the opposition Liberal Party's Benigno "Noynoy" Aquino, son of former President Corazon Aquino.
Also running are billionaire Senator Manuel "Manny" Villar and former President Joseph Estrada, who was ousted in 2001 allowing his vice-president, Mrs Arroyo, to take over.
She was re-elected in 2004 amid allegations she attempted to rig the vote.