These three words are a critical development in the Bronwyn Bishop expenses

Amid further revelations of Mrs Bishop using travel entitlements for personal reasons and her ongoing refusal to address the claims, Liberal MPs, sick off having to defend the Speaker, believe the issue could overshadow the return to Parliament on August 10 and even play into the Canning by-election, caused by the death of Don Randall. “Bronwyn Bishop has to go”, he said.

Mrs Bishop has been engulfed in a furore over her use of taxpayer-funded political entitlements, after it was revealed that she spent ,227 on a charter helicopter to travel a short distance from Melbourne to Geelong for a political fundraiser.

Bishop claims she was in Albury on official business on the weekend of Sophie Mirabella’s wedding in June 2006-but she has refused to provide documentation of the meetings, and claims she must keep the detail top secret to protect the anonymity of the people she met with.

News Corp has reported that Mrs Bishop charged taxpayers $288 in travel allowance to stay in Brisbane on the night of Liberal MP Teresa Gambaro’s wedding in 2007.

It’s time for Madame Speaker to cough up and provide the proof that these were indeed business trips-or it’s time for her to step down.

Opposition Leader Bill Shorten suggested she be replaced with Queensland Liberal National MP Bruce Scott who has served as Deputy Speaker for three years.

“Put simply, Mr Abbott has to act”.

Mrs Bishop is refusing to do so saying committee chairs are allowed to conduct independent research without requiring the rest of the panel’s approval.

“The Speaker is consulting with her colleagues and I think that’s the appropriate place for those discussions to take place”.

There is broad agreement among those the ABC spoke to that the continuing scandal surrounding Mrs Bishop is damaging the Government.

Mrs Bishop’s use of taxpayer money has been attracting scrutiny for a fortnight and it is set to flare again when Parliament resumes in a week-and-a-half.

But a spokesman for Mrs Bishop told Fairfax Media on Wednesday “the Speaker is not resigning and will not be resigning”.

But the Finance Department is inquiring into that charter flight and two others and has not yet made a declaration.