The Philippines' Mining Industry Coordinating Council has delayed the review of 26 mines in the country ordered closed or suspended in 2017, with the Department of Finance saying the final outcome of the assessment is now scheduled to take six months instead of three, Bloomberg News reported March 27.

"All administrative and judicial remedies have to be exhausted for the orders to be final and executory," Environment Undersecretary Jonas Leones was quoted as saying.

The review will begin in March and initially cover legal, technical and environmental concerns before moving on to the social and economic aspects. The delay could mean the study will not be prepared before August, after an earlier pledge to complete it by the end of 2017.

The delay is creating uncertainty over the country's nickel ore supplies. According to Chinese customs data, the Philippines exported 29.1 million tonnes of nickel ore to China in 2017, down from 30.6 million tonnes in 2016.

Regina Lopez, the country's former environment minister, led a mining crackdown, ordering the closure or suspension of 26 mines and canceling 75 mining contracts for underdeveloped mines in order to protect watersheds.

Leones noted that the miners are appealing the closure orders and that their projects are still operational.