Filipino troops have declared an eight-hour "humanitarian" ceasefire in the besieged town of Marawi to allow Muslim residents to celebrate Eid al-Fitr, which marks the end of the month of Ramadan.

There is a large population of Muslims in the island of Mindanao, where Marawi is located, but the rest of the country is predominantly Roman Catholic population.

Military chief General Eduardo Ano ordered his forces to observe a "humanitarian pause" during Eid on 25 June, AFP reported.

"We declare a lull in our current operations in the city on that day as a manifestation of our high respect to the Islamic faith," he said in a statement.

Filipino troops have been fighting against Maute and Abu Sayyaf militants – affiliated to the Isis terror group – since 23 May, when fighters seized the town in retaliation to the army's failed attempt to capture terrorist leader Isnilon Totoni Hapilon.

Fighting has caused the death of nearly 300 militants, 67 troops and 26 civilians, prompting President Rodrigo Duterte to declare martial law in Mindanao.

More than 200,000 people have also been displaced, with the army estimating at least 500 civilians remain trapped in areas where fighting is concentrated.

Their lives are at risk due to bombings, starvation as well as the militants' use of civilians as human shields.

"We will continue to try to enter the areas occupied by them and liberate Marawi", military spokesman Brigadier General Restituto Padilla said during an interview on radio DZBB.

The army said earlier in June it was confident it could recapture the entire town within few days. However, fighting has continued since.

Some reports have claimed US special forces have joined the Filipino army in its fight to drive militants out of Marawi, something that Duterte said he was not aware of. The leader, who earlier this year said US troops stationed in the Philippines had to leave, claimed he "never approached America" for help.

Australia has sent two high-tech surveillance planes to help troops.

Earlier in June, the army said it believed Hapilon was still hiding in Marawi's Barangay Lilod Madaya area.

However, a senior military commander is now claiming Hapilon may have fled Marawi. The army is investigating the claims.

Marawi Philippines Maute
Government soldiers go door to door, looking for Maute group insurgents, while conducting a security inspection in Marawi Romeo Ranoco/Reuters