Tony Abbott has hosed down claims lobbyists are buying influence within the Liberal party, saying the only alternative to private political fundraising would be a slug on taxpayers.

Joe Hockey is facing questions about whether or not he offered privileged access to business and industry lobbyists in return for annual political donations.

While the donors' identities remain confidential, Fairfax Media alleges he offered access to members of the North Sydney Forum, a campaign fundraising body run by the North Sydney Federal Electoral Conference, which itself is linked to the Liberal party.

A spokeswoman for the treasurer said any suggestion the North Sydney MP was “for sale” was "offensive and repugnant".

The prime minister said he had not read the story, but added it was typical for government figures to attend fundraising events.

"All political parties have to raise money," he told the Nine Network on Monday. "The alternative to fundraising in this time-honoured way is taxpayer funding." It would be wrong to consider slugging taxpayers at a time of budget austerity, he said.

Abbott also played down calls for a federal anti-corruption body, like the NSW Independent Commission Against Corruption, saying Canberra had a "pretty clean polity" and people should be careful about "casual smearing".

Hockey's Liberal colleague Josh Frydenberg said the treasurer had done nothing untoward: "This is an absolutely outrageous story," he said.

But the Labor frontbencher Andrew Leigh said the report showed how much it cost to be Hockey's "friend".

"Joe Hockey likes to give the impression that he's everyone's friend," Leigh told Sky News. "But now we learn it costs $5,500 to be a friend of Joe's, or $11,000 if you want to be a friend with benefits."

The Australian Greens said the treasurer should reveal details of who belongs to the North Sydney Forum – and the prime minister should follow suit and reveal who belongs to the Warringah Forum in his nearby electorate.

"These two forums effectively sell access to the two most powerful politicians in Australia," NSW senator Lee Rhiannon said. "Wealthy individuals and companies donate money to election campaigns through these shady organisations but the public is not informed of these connections. This is unacceptable."

