The Speaker is under further pressure as revelations emerge that she hired a corporate aircraft to travel from Sydney to Nowra for a Liberal party fundraiser.

Bronwyn Bishop reportedly spent more than $6,000 to hire a luxury corporate aircraft to transport her 160km from Sydney to Nowra – a journey of just over two hours by car.

The trip, to attend a Liberal party fundraiser in Berry, came two weeks after the Speaker controversially took a helicopter ride from Melbourne to Geelong, News Corp Australia reports.

Bishop was forced into an apology after it was revealed she charged taxpayers more than $5000 for the trip to a fundraising event.

Bishop’s chief of staff, Damien Jones, would not comment on the cost of the Nowra flight, which took place last year.

“I haven’t looked at the costs so I can’t comment. My discussions will be directly with the Department of Finance,” he told News Corp.

When Jones was asked by News Corp if the company that provided the aircraft to Nowra was the same one that provided the helicopter between Melbourne and Geelong, he said: “It could well have been. I don’t have that information.”

He said the aircraft was a propeller plane, not a corporate jet.

Tony Abbott has indicated he could consider further changes to the rules governing parliamentary entitlements following the controversy over the Speaker’s use of chartered helicopter and her travel claims.

“I think if there is one lesson that every single politician must have had reinforced by all of this, it is that you cannot get away with exploiting the rules,” the prime minister said.

“We have already significantly tightened up the rules. We banned politicians travelling overseas first class, we’ve heavily limited family travel inside Australia and overseas, we’ve banned immediate family employment,” he said on Sydney radio on Friday.

These are the 15 trips Bronwyn Bishop claimed when hearings were not held

The claims, amounting to $3,723, cover three separate inquiries of the standing committee on families and human services.

“As for Bronny, she’s repaid the money with penalties. She is obviously deeply remorseful, anyone who saw her on television yesterday would know that this is a very, very chastened person indeed.”

Bishop, who is under increasing pressure to stand aside as Speaker over the travel claim controversy, said on Thursday she would repay travel allowance and airfare claims made on some of the dates, which she has said were justified because of secret meetings with unnamed sources associated with her committee work, but which also coincided with the interstate weddings of two Liberal colleagues.

She has said the claims were “technically within the guidelines” but “didn’t look right” and revealed she had asked the finance department to review all her travel claims.

After three weeks of refusing to apologise, Bishop said on Thursday she was “sorry” for “letting the Australian people down” over the travel claims and controversial helicopter flight.

Bronwyn Bishop expenses row: historic claims reveal another 15 trips

With the Speaker under increasing pressure to stand aside, further claims reveal that as a committee chair she claimed travel benefits even when the committee was not conducting hearings.

The Department of Finance is reviewing all of Bishop’s expense claims over the past decade. Abbott said while his government had already tightened the rules, there may be more changes to come.

“Let’s see what else might emerge out of the review that’s going on now,” he said.

One Liberal backbencher, Brett Whiteley, has written to the Speaker expressing the concerns of his Tasmanian electorate about the expenses revelations.

“The community is understandably angry about this issue. Everyone makes mistakes, including members of parliament, and I am pleased to hear the Speaker’s genuine apology on commercial radio,” he told the Hobart Mercury on Thursday. “I have written to the Speaker to inform her directly of the views of my electorate, and both their and my disappointment in the serious entitlement misjudgement.”