Bronwyn Bishop defends taxpayer-funded travel to colleague Sophie Mirabella's wedding as 'official business'

House of Representatives Speaker Bronwyn Bishop has defended her use of taxpayer funds to attend a colleague's wedding.

Prime Minister Tony Abbott has placed Mrs Bishop "on probation" for her use of taxpayer funds to charter a helicopter to attend a Liberal Party function in Victoria in 2014.

Mrs Bishop is paying back the $5,227 cost of the charter, plus a 25 per cent penalty.

Mrs Bishop's office has now confirmed the Speaker claimed the $600 cost of return flights to Albury in 2006, from where she travelled to former frontbencher Sophie Mirabella's wedding in Wangaratta.

A spokesman for the Speaker said she was in Albury on parliamentary business.

"She was on official business, as the chair of the family and human services committee," he said.

The committee was holding an inquiry into work and family balance at the time, but did not hold any public hearings in Albury.

Mrs Bishop's spokesman said it was common for committee chairs to meet people on their own as part of an inquiry, but was unable to provide more details about her meeting in Albury.The spokesman said Mrs Bishop did not claim the cost of road transport or accommodation in relation to the wedding.

Mr Abbott claimed the cost of attending Ms Mirabella's wedding in 2006, but later paid it back.

Federal Opposition spokesman Pat Conroy said that implied Mrs Bishop should also repay the money.

"If Tony Abbott thinks it's OK to go to a wedding and charge the taxpayer for it, why did he pay the money back?" he said.

"And if he thinks it's not OK, why hasn't he asked Bronwyn Bishop to repay the money?

"Is there anything Bronwyn Bishop actually pays for herself — without being forced to, of course?"