Peter Dutton says he paid his own way to Gina Rinehart’s 70th birthday bash last week

The Opposition Leader copped questions about who funded his round-trip to celebrate Gina Rinehart’s birthday party last week.

Peter Dutton has defended crisscrossing the country to attend mining billionaire Gina Rinehart’s extravagant birthday party last week, saying he paid for his own flight after being questioned over taxpayer costs.

The Opposition Leader, whose close relationship with Australia’s richest woman has been well documented, raised eyebrows after he reportedly flew nine hours to Perth to attend Ms Rinehart’s 70th birthday bash only for less than 60 minutes.

Mr Dutton then hopped on a red-eye flight to Melbourne to attend a Dunkley campaign event early on the following Friday, the Australian Financial Review reported.

Asked if it was appropriate to use taxpayer funds required for the security detail and comcars needed to escort him on the trip, Mr Dutton said he was “very proud” to have been there.

“I consider her [Ms Rinehart] to be a dear friend, a great Australian,” he told reporters in Perth on Wednesday.

“If people in the Labor Party want to trash Gina Rinehart as Australia’s most successful businesswoman, let them, instead of making background comments, come out and say that.

An economy class Qantas red eye ticket from Perth to Melbourne would cost about $376. Picture: NCA NewsWire / Jeremy Piper

“Gina, through her companies, employs thousands of people here in WA … if people want to speak negatively about her that’s an issue for them.”

But when pushed by reporters to answer to his publicly funded expenses, Mr Dutton pointed to the fact that he did not stay at the event overnight.

“I flew back on the red-eye so that I could be in back Melbourne at 4.30 the next morning. So that’s how it works,” he said.

Ms Rinehart, who has a whopping net worth of $37.4bn, celebrated her birthday by throwing a lavish black-tie event on the banks of Perth’s Swan River last Thursday night.

The bash reportedly featured a horseshow and a performance by Guy Sebastian, who sang the national anthem.

One Nation Senator Pauline Hanson also attended, according to reports.

Mr Dutton’s presence at the party was first called into question by 2GB Host Ben Fordham, who asked on his show last week why the Liberal leader was not in Dunkley to drive campaign efforts ahead of the by-election planned for that Saturday.

Prime Minister Anthony Albanese came under similar heat a week prior after he was spotted at a party at the Melbourne mansion of recycling billionaire Anthony Pratt.