President Rodrigo Duterte's advice to the public to disinfect their masks using gasoline was just a "joke," Malacañang said on Thursday.

During his taped message aired on July 21, Duterte reminded the public to disinfect first the mask, if it is reusable, before using it again.

He said the people could spray the masks with alcohol or Lysol.

"Those who cannot afford, soak it in gasoline or diesel, that COVID is son of a b****. It will be killed there. That's true. If you don't have (other disinfectants), if you want to disinfect, find gasoline," he said.

His advice of using gasoline went viral on social media.

But in a virtual press briefing, Presidential Spokesperson Harry Roque said Duterte's advice was just a joke.

"The President has been (in office) for four years, as if you don't know yet the President. Joke only! Why would we wash using gasoline," he said.

He even reiterated that as much as possible, Duterte wants to give free masks to the people.

"I will try to buy as many as I can afford, we will give it free but wear it, and may be you can use it twice for as long as you will spray it with alcohol after," Duterte said during his televised message. Celerina Monte/DMS