Philippine president Rodrigo Duterte stepped up efforts to bring peace to the country's insurgency-hit south during a visit there on Thursday, calling upon the Islamic militant group Abu Sayyaf to end its campaign of violence.

Speaking to local military and government leaders on the troubled island of Basilan, a base of the Abu Sayyaf group, Duterte said: "I am pleading for peace, even with the Abu Sayyaf. You have committed crimes, killing people... You are not thinking of anything but hatred."

But Duterte, the first president to hail from the south and who claims Muslim ancestry, added that "every Filipino life is precious" and "we have to stop this war".

The Abu Sayyaf is a loose network of a few hundred Islamic militants formed in the 1990s with seed money from Osama bin Laden's Al-Qaeda network that has earned millions of dollars from kidnappings-for-ransom.

It is a radical offshoot of a decades-long Muslim separatist insurgency in the south of the mainly Catholic Philippines that has claimed more than 100,000 lives. The main Muslim rebel groups do not generally engage in kidnappings-for-ransom.

Duterte is known for his hardline stance against crime, even boasting of killing numerous criminals, but he he has called repeatedly for talks with all rebel groups.

Despite his message of peace, Duterte warned that if the group did not lay down its arms "soldiers will keep coming. That is the response of government".

His visit came as troops were battling the Abu Sayyaf in the hinterlands of Basilan.

The military has said at least one soldier and over 30 Abu Sayyaf fighters were killed in weeks of fighting there.

Although its leaders have pledged allegiance to Islamic State, analysts say they are mainly focused on lucrative kidnappings.

While Duterte addressed troops, his chief peace negotiator Jesus Dureza held meetings with the country's largest Muslim rebel group, the Moro Islamic Liberation Front (MILF), elsewhere in the south.

The 12,000-strong MILF had hoped to seal a final peace deal under Duterte's predecessor, Benigno Aquino, but legislators delayed passing legislation needed for the plan.

A ceasefire with the MILF, in place since 2003, has largely held but the Abu Sayyaf are not covered by the truce.

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