The Philippine president has warned that a collapse of a recent peace deal with the largest Muslim rebel group would help terrorists. Some lawmakers have questioned the deal after rebels were involved in a weekend clash that killed 44 police anti-terror commandos.

President Benigno Aquino III called Wednesday for support for the pact with the Moro Islamic Liberation Front, but also said he expects the group to help authorities identify the insurgents who killed the elite policemen in fierce fighting.

Officials say the clash Sunday was a "misencounter" with the rebels while the commandos were on a separate mission to capture two terror suspects in a remote southern town.

The fighting shattered years of relative calm in the south.