"We are disgruntled on how the President had reached such a decision. It falls upon the President to prove that the abolition is not politically motivated and is not unjust," said the CIU in a statement signed by its national chairwoman Emaco Mercedita Naldoza.
President Arroyo recently issued Executive Order 149 ordering the immediate deactivation of the SPDA and declaring all its executive positions vacant.
The President created a task force, headed by Presidential Assistant for Mindanao Jesus Dureza, to oversee the deactivation process.
Leaders of the Moro National Liberation Front has dismissed EO 149 as a "mockery" and "flagrant violation" of the 1996 peace agreement, fearing about its repercussions on the peace process since the agency has been implementing socio-economic projects in areas covered by the accord.
The CIU said EO 149 has "shocked" and "brought untold misery" to SPDA employees who would be jobless this coming year.
"This is a heartless and inhuman decision by the President as the families of these employees are now facing a blank wall on how to meet their basic needs, their daily subsistence, the education of their children," the CIU said.
The CIU is the umbrella organization of the Concerned Alliance and Union of SPDA Employees.