Rodrigo Duterte will also hold talks with military and police officials following blasts at the Roman Cathedral of Our Lady of Mount Carmel on the island of Jolo.
The Filipino bishop, Efraim Tendero condemned the "evil act" as he called upon authorities to ensure "all the perpetrators are brought to justice".
Bishop Efraim, who is general secretary of the World Evangelical Alliance (WEA), said: "The WEA strongly condemns this evil act that runs against the peaceful teachings of both Islam and Christianity who both respect each other's places of worship and prayer.
"We prayerfully affirm the work of the Christian and Muslim peacebuilding advocates and field workers who have been doing advancing the cause of justice and peace for decades.
"We call on the authorities to immediately initiate an impartial investigation until all the perpetrators are brought to justice and until all the victims are fully served with just compensation and reparation.
Islamic State (IS) claimed responsibility for the attack, which has left more than 100 people hurt.
Militants from the IS-aligned group Abu Sayyaf have been carrying out bombings, kidnappings and beheadings in the region during recent years.
A bloody separatist movement has left nearly 150,000 died during the last almost-five decades.
An approximately minute-long delay between the explosions appears to have increased their deadly toll; military troops and police responding to the first were caught up in the second.
In a bid to prevent similar attacks, police across the country have been put on heightened alert.
According to the SITE Intelligence monitoring group, a communique by IS claimed the attack was carried out by two suicide bombers wearing explosive belts. The claim could not be independently verified.
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