A senior federal minister is adamant it is appropriate for politicians to claim travel expenses for sporting events.

Trade Minister Steve Ciobo says he did nothing wrong in charging taxpayers more than $1,100 to travel to the AFL grand final in 2013, saying such sporting events are work related.

Mr Ciobo is one of a number of federal politicians under pressure to explain their expenses, with Health Minister Sussan Ley stepping down from the frontbench amid an investigation into her travel claims.

Mr Ciobo was unapologetic on the issue, telling the ABC that taxpayers would expect to pay for such expenses.

"I'm sorry, but the reason I was invited isn't because I'm Steve Ciobo — I was invited because I'm the Trade Minister," he said.

"Ministers or parliamentary secretaries or others are invited to go along to these events specifically by businesses and organisations who are taking the opportunity to showcase themselves there, to take the time to have a conversation in relation to important matters, absolutely [it] is work related."

Mr Ciobo also defended Prime Minister Malcolm Turnbull, who is yet to front the media over the issue.

"I don't believe the Prime Minister needs to come out on each and every single issue that's running each and every single day," he said.

Sorry, this video has expired Should taxpayers pay for politicians' sports tickets?

Acting Special Minister of State Kelly O'Dwyer said changes would be made to the parliamentary entitlements system within the next six months, following a review instigated by former prime minister Tony Abbott.

The review, undertaken after former speaker Bronwyn Bishop used chartered helicopters to attend party fundraisers, resulted in 36 recommendations.

But crossbench MP Andrew Wilkie said reform was not happening fast enough.

Mr Wilkie told the ABC action was needed after the "terrible judgement and quite improper spending" uncovered.

"The Government in the last few days has said that they will move to implement them finally, but I note that in March last year, the Government said exactly the same thing," he said.

"Words are pretty worthless in Canberra these days."

Crossbench senator Nick Xenophon is set to reintroduce a bill next month that would mean harsher penalties for breaches of politicians' entitlement rules.

Senator Xenophon's push to tighten the system was rejected by the Coalition and Labor in 2015.