President Rodrigo Duterte said on Monday he will declare September 21 as a "national day of protest" and government work and classes will be suspended.

In an interview in Caloocan City, Duterte, however, said September 21 is "not a holiday."

He said the communist New People's Army and others who want to protest against the government as well as the police and the military could participate.

"Red Army come down here. I will not arrest you," Duterte said.

But he warned the leftist rebels not to commit any crime, including vandalism.

He said the police and the military will be confined in the barracks during that day.

Duterte said even government employees who are part of unions can also join the protest.

September 21 coincides with the 45th anniversary of martial law declaration by late dictator Ferdinand Marcos.

Different groups who have been critical of the Duterte administration are planning to hold rallies on that day. Celerina Monte/DMS