The Philippine government will start the extradition proceedings of a Filipino physician accused of plotting terror attacks in the United States, Malacanang said on Sunday.

In a statement, Presidential Spokesperson Ernesto Abella said the Palace confirms that Russel Salic, who has been charged for allegedly supporting a foiled terror plot in New York City, is now under the custody of the National Bureau of Investigation.

"The Philippines shares information and extends full cooperation with partners on matters pertaining to terrorism, and in the case of Dr. Salic will include initiating extradition proceedings being requested by the US," he said.

He said Salic was said to be the physician attending to the Islamic State-inspired Maute terrorists, who have been occupying Marawi City since May 23.

The Palace official said the Filipino doctor is currently undergoing preliminary investigation before the Department of Justice over kidnapping and murder charges.

"The preliminary investigation of the case against Mr. Salic will continue while extradition proceedings are being processed," Abella said.

The US authorities have said that Salic and two other IS sympathizers were supposed to carry out terrorist attacks at New York City locations, including concert venues, subway stations, and Times Square in the summer of 2016.

But the planned attacks were foiled following the help of a Federal Bureau of Investigation undercover agent.

Philippine authorities have been pursuing terrorists in Marawi City since May. The Armed Forces of the Philippines has said that they would soon complete the clearing operations of militants in the city. Celerina Monte/DMS