Washington: The United States is weighing additional support to the Philippine military as it fights an Islamist insurgency in the south, a US defence official said Tuesday.

Discussions are “pretty advanced” and would see the US provide increased surveillance drone capabilities and training for local forces, the official told AFP on condition of anonymity.

The drones could hypothetically be used to conduct strikes, the official added, although that would only be for self-defence reasons to protect US or partner forces, and would not signal another front in America’s drone wars.

“It’s not necessarily what those (drones) are there for. Those are there for ISR and support,” the official said, using an abbreviation for intelligence, surveillance, and reconnaissance.

The Philippines’ Department of National Defence said there had been no discussions regarding the use of US drones to strike Daesh-inspired “terrorist groups.”

Pentagon spokesman Lieutenant Colonel Chris Logan said all military assistance in the Philippines is conducted at the request of the government.

“We respect the sovereignty of the Philippines, and we are not pursuing unilateral action in the Philippines,” he said.

Philippine President Rodrigo Duterte has asked lawmakers to approve the recruiting of 20,000 more soldiers to tackle increased security threats following a bloody urban siege in the south.

Almost 700 people have been killed, according to the official count, in over two months of fighting in the southern city of Marawi against Islamist militants who have pledged allegiance to Daesh.

The militants, waving the black Daesh flag, have occupied parts of Marawi since May 23, prompting Duterte to declare martial law in the entire southern region of Mindanao.

US Secretary of State Rex Tillerson on Monday called the crisis in Marawi a “tragic situation” and said US forces were providing surveillance aircraft and important advice for the Philippines forces in the battle there.

The US has for years provided intel to the Philippines and has between 300 and 500 special operations and regular forces stationed in the country.