MANILA -- It will be "almost impossible" for the Philippines to be be "drug-free" unless the government succeeds in curbing demand, Senate President Vicente "Tito" Sotto III said Tuesday.

Drug dependents "will look for something to abuse" even if authorities destroy all illegal drugs, the author of the country's anti-drug law told reporters.

"We have to look into the possibility of a drug-resistant country instead of drug-free," Sotto said.

A drug-free country "at this point, is almost impossible, because we have not been successful in the other half of the fight which is demand-reduction strategy," he said.

Authorities are waging a war on drugs, initiated by President Rodrigo Duterte who was elected to office in 2016. International groups said the campaign gave rise to abuse by security forces.

According to a police count, 5,526 drug suspects were killed from the first day of Duterte's term July 1, 2016 until June 30 this year. The slain suspects were accused of fighting back while resisting arrest.