While he may disagree with the views of anti-Marcos protesters gathering in Manila on Friday, he will defend their right to speak, President Duterte said during his visit to wounded soldiers in Zamboanga City on Friday.

"I may disagree by what you say, but I will defend your right to say it. Those are borrowed terms," he said to Black Friday protesters who converged at the Quirino Grandstand in Manila to express outrage over the hurried burial of late strongman Ferdinand Marcos at the Libingan ng mga Bayani.

• READ: Anti-Marcos forces mount 'Black Friday' protest

Duterte was quoting a line which appeared in a book by English writer Evelyn Beatrice Hall, which is often used in reference to freedom of expression.

However, earlier, Duterte said government forces would not be able to control any possible conflicts that may happen should Ilocanos come to Manila to confront anti-Marcos protesters.

"Almost 98 percent of all Ilocano-speaking regions," Duterte said, hold ill feelings for the delay in giving Marcos, who hails from Ilocos Norte, a burial they feel their hero deserves.

"'Pag magbabaan lahat iyan sa Manila…'pag may mga 30,000 or 50,000 na mag-demonstrate diyan sa city nila (If they all go down to Manila, if 30,000 or 50,000 demonstrate)…can we control it? Can the military control it? Of course not, because I would not allow them to bring rifles. It would only be the police. What would happen?" Duterte said.

"Ilan kaya ang mamatay sa bugbugan o if anybody carries a gun?
Ako iniisip ko lahat. What would be the impact of this on the Ilocandia?"

Marcos was hurriedly buried at the Libingan ng mga Bayani Friday last week, in ceremonies closed to the public.

The "surprise" burial, of which Duterte denied any concrete knowledge, was met with protests from victims of Martial Law and their supporters.