Malcolm Turnbull is "very, very concerned" about Home Affairs Minister Peter Dutton's meeting with a Chinese billionaire now banned from re-entering Australia.
The former prime minister pressured his replacement Scott Morrison to urgently investigate Mr Dutton's meetings with Huang Xiangmo, but Mr Morrison says he's not worried about it.
"I have spoken to Peter Dutton about this. There are no issues here that troubled me at all," Mr Morrison told reporters in Tasmania on Tuesday.
Mr Huang paid tens of thousands of dollars to a lobbyist in 2016 to secure a private lunch with Mr Dutton when he was immigration minister in a failed attempt to fast track his citizenship application, it's been claimed.
The now-Home Affairs Minister said he agreed to the meeting because Mr Huang was a significant leader in the Australian Chinese community.
"I've never received a dollar from this individual. I had that one meeting with him over lunch. I haven't seen him since. What's he got from me? Well, he's now offshore," Mr Dutton told reporters in Rockhampton.
But Mr Turnbull said Mr Dutton and lobbyist Santo Santoro - a former Liberal government minister - have a lot to explain about the "very troubling" revelations.
"Scott Morrison is the prime minister and you can't wave this off and say it is all part of gossip and the bubble. This is the national security of Australia," Mr Turnbull told reporters.
"I think it is very, very concerning and very troubling for anyone.
"This has to be addressed at the highest level of security, priority, urgency by the prime minister. The buck stops with him."
Mr Morrison said Mr Huang had his Australian visa cancelled while he was out of the country.
"So if the object was foreign interference, well, the exact opposite is what has occurred," he said.
"I think when it comes to these issues our government's record is squeaky clean."
Labor senator Sam Dastyari, who was forced to resign after it was revealed he tipped Mr Huang off about an investigation into him, tweeted a link to a news story about the meeting with Mr Dutton and said: "I resigned for less."
Mr Huang paid Mr Santoro and then met with Mr Dutton at a Chinese restaurant in Sydney, according to an investigation by the ABC's Four Corners.
The minister has denied his citizenship bid was discussed at the meeting.
He lost his bid after ASIO raised his links to the Chinese Communist Party and he was later banned from Australia on national security advice.
The investigation also said Mr Dutton approved a request from Mr Dastyari to fast track Mr Huang's family's application and allowed them a private citizenship ceremony inside the former Labor senator's parliament house office.
Labor argues the incident strikes at the integrity of Australia's immigration system and Mr Dutton's performance as a minister.
"(This is) one of the ministers in charge of national security where it is cash for access and meeting people connected to the Chinese government. This is very unhealthy," Labor leader Bill Shorten told reporters in Gladstone.
