Duterte denies aide intervened in Philippines warship deal

The fiery-tongued Duterte, who has long insisted he would fire any official at the slightest "whiff" of corruption, challenged the media to produce evidence of wrongdoing so he could sack his righthand-man Christopher "Bong" Go.

In an angry outburst, he accused local news website Rappler, which first reported the allegations, of publishing "fake news".

"That kind of talk, 'intervenes' -- especially in the sale of ships! What will people say: 'Son of a whore, corruption again!'," the president told reporters.

"You can stop your suspicious mind from roaming somewhere. But since you are a fake news outlet then I am not surprised that your articles are also fake," he told a Rappler reporter.

"The things that you are telling here never happened."

The government signed a contract in 2016 with South Korean shipbuilder Hyundai Heavy Industries to build two frigates to be delivered to the Philippine navy in 2020 and 2021.

But concerns were raised last month as the commander of the Philippine Navy was abruptly sacked for delaying the project.

Defence Secretary Delfin Lorenzana claimed Vice Admiral Ronald Joseph Mercado was trying to force the government to award a separate contract for the warships' "combat management systems" to a specific electronics company.

Mercado was removed from office following "instructions from higher authorities", according to military officials.

While Mercado has not yet responded to Lorenzana's allegations in public, Go on Tuesday issued a statement denying any malpractice, saying he had not participated "nor intervened directly or indirectly in the transactions".

"I have not intervened in the procurement of the computer system for its (the defence department's) ships," Go said.

The allegations come as the government seeks to shut down Rappler, a website critical of Duterte's brutal war on drugs that has left nearly 4,000 suspects dead.