"A world without facts means a world without truth and trust," Ressa said during a livestreamed interview with her news website Rappler.

The outspoken critic of President Rodrigo Duterte expressed "shock" at the award and said Rappler, the news outlet she co-founded, "would just keep doing what we're doing."

Ressa and Rappler have faced multiple criminal charges and investigations after publishing stories critical of Duterte's policies, including his bloody drug war.

The former CNN correspondent is on bail pending an appeal against a conviction last year in a cyber libel case, for which she faces up to six years in prison.

Two other cyber libel cases were dismissed earlier this year.

"In less than two years the Philippine government filed 10 arrest warrants against me -- it was pretty bleak at different times," Ressa said.

Nonetheless, she was defiant in her defence of her battle for freedom of expression and independent journalism.

"This is the best time to be a journalist," Ressa said as she smiled. "The times when it's most dangerous are the times when it's most important."

In April, the UN's cultural agency awarded its annual press freedom prize to Ressa in recognition of her "unerring fight for freedom of expression".

"We need to continue shining the light," Ressa said. "We need to continue doing accountability journalism."