"We call on all those who can no longer endure this wrongful governance with its structures of evil and unmoderated greed: it is time to cut clean, it is time to go," read the statement, signed by the ex-officials, including five former finance chiefs and former central bank governor, Jose Cuisia.
A Senate probe into allegations of $130 million worth of kickbacks in a state telecoms deal with China's ZTE Corp. has revived calls for the resignation of Arroyo and opposition groups are planning anti-government rallies next week and on Feb. 25, the anniversary of the overthrow of dictator Ferdinand Marcos.
On Sunday, former president and democracy icon Corazon Aquino joined around 2,500 people at a church service in Manila to honour Rodolfo Lozada, a former government official whose testimony in the Senate inquiry revived the protests.
"I want all of us Filipinos to be united again. If we can get together we will also see a bright future for our country," Aquino told the cheering congregation, who finished the mass with a protest song and clenched fists.
Aquino was elected president in 1986 after Marcos was overthrown in a people power revolt.
A spokeswoman for the presidential palace cautioned against political manoeuvring.
"Disunity and discord will only bring our country down from the gains we have achieved," said Lorelei Fajardo.
A presidential election is not due until 2010 when Arroyo's final term ends.
Güncelleme Tarihi: 17 Şubat 2008, 15:44
Arroyo has survived three impeachment bids and at least three coup plots since coming to power in 2001 and political analysts have said she will likely see out the remainder of her term because she has the support of the military and the lower house of Congress.
But Scott Harrison, a risk consultant, said Arroyo's position was safe for now.
"It has to go a lot further than this before she has something serious to worry about," said Harrison, managing director of Pacific Strategies and Assessments. "Today Cory (Aquino) did not call for Arroyo to resign, that's significant."
He said Arroyo's position would be only be jeopardised if a senior member of the administration called for her downfall, or the powerful Catholic Church spoke out strongly against her.
But allegations of multi-million dollars worth of kickbacks have outraged many middle-class Filipinos.
"We are here not only to support Lozada, because we believe there is corruption we have to do something about it and let the truth come out," said Antonio Luistro, a father of five, at the Sunday's church service.
On Friday, around 10,000 people gathered in Manila's financial district calling for Arroyo to go, the biggest crowd since tens of thousands demonstrated against her in 2005 amid allegations she cheated in the 2004 election.
Opposition groups are hoping the protests will gather steam.
"We are seeing a lot of the middle class, businessmen and professionals," said Ronald Llamas, the head of Akbayan, a civil society group. "In the past we had a hard time convincing them to join us. Now they are voluntarily joining in."