President Rodrigo Duterte on Monday fired a veiled insult at the integrity of a lawmaker poring over alleged overpriced government transactions during the COVID-19 pandemic.

"Tanungin ko si (I will ask) Panfilo Lacson: are you honest? Answer me truthfully, are you honest?" Duterte said in a taped speech that aired on Tuesday.

"Kung magsabi ka yes, sasagutin kita next program, may ipakita ako," he said, addressing the senator.

(If you say yes, I will answer you in the next program, I will show something.)

Duterte did not give more details.

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Earlier in his speech, Duterte hurled insults at Lacson's hairstyle and the physique of Sen. Richard Gordon, chairman of the Senate Blue Ribbon committee which is leading the investigation.

"The Senate will not flinch on this one," Lacson said of the probe.

He said Duterte had been spewing "incoherence and senseless ad lib even in his formal addresses to the nation."

"That said, it is not difficult to think that he is in panic mode and is attempting as he has already done earlier to discourage the Senate from pursuing our investigation in the highly anomalous procurement of overpriced medical supplies that is starting to knock on the doors of Malacañang," the senator added.

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