Labor is questioning why Scott Morrison refused to admit he was wrong after twice mistaking Australia's policy towards Taiwan for the government's position on Hong Kong.
The prime minister last month referred to a "one country, two systems" approach towards Taiwan in two interviews.
In the second appearance, he denied making a mistake despite his description matching Australia's stance on Hong Kong.
But the government issued a clarification confirming Australia's position was unchanged.
Opposition foreign affairs spokeswoman Penny Wong wants to know why he didn't front up and admit the error.
"What I don't understand is why he then lied about it," she told a Senate estimates hearing in Canberra on Friday.
"Why doesn't he just say 'yes I misspoke'? He used the wrong phrase."
Foreign Minister Marise Payne said Australia's "one China" policy on Taiwan had not changed.
"The prime minister's comments on one country, two systems are a reference to Hong Kong," she said.
"I've seen the commentary and I've seen the statements. I know the prime minister recognises the one country, two systems description is in relation to Hong Kong."
But Senator Payne said she couldn't speak for Mr Morrison after being asked why he didn't own up to the mistake.
"I don't agree it's appropriate to say the prime minister lied. The government's position is clear," she said.
"The prime minister's office did release the statement the senator has referred to which reinforced our long-held position."
Committee chair and Liberal senator Eric Abetz called for Senator Wong to withdraw the accusation that Mr Morrison had lied.
Senator Wong asked the foreign minister if the prime minister usually acknowledges mistakes.
"Prime ministers broadly speaking, all of us as humans, acknowledge that we make mistakes. I certainly do," Senator Payne said.
Department of Foreign Affairs and Trade officials said they were not consulted about the official clarification made after Mr Morrison's interviews.
Australia has for many decades maintained a "one country" policy on Taiwan.
The policy distinction has come into sharp focus as the prospect of military conflict between China and Taiwan continues to grow.