Opposition Leader Tony Abbott's anti-carbon tax campaign hit a snag at a Canberra butcher today where a scheduled media conference was abruptly canned.

It is Mr Abbott's custom to invite journalists, photographers and camera crews to observe him daily in a Liberal-friendly business, filleting a fish or driving a nail, and today was to be no different.

But it was far from business as usual. Reporters arrived at The Butcher Shop in Dickson at 10am to find one of Mr Abbott's staffers blocking their entrance and no sign of the Opposition Leader.

The picture opportunity had apparently been given the chop.

The gathered throng were told the butcher did not want to talk to them, but they, by now, were very keen to talk to the butcher. What was his beef about?

ABC News Online rang the butcher to ask why the visit had been canned only to be told: "Can't help you mate. Have a great day."

The unusual turn of events comes as Mr Abbott continues his campaign against the Government's carbon pricing scheme which is to be introduced into Parliament next month.

Mr Abbott refused to address suggestions that business did not want him there, saying instead that it was his own decision to change the venue.

"The visit had long been pre-arranged. It had been fully discussed with the business proprietor, all systems were go and then once the media alert went out the business received, as I understand it, an aggressive phone call.

"I thought under those circumstances it was best to change the venue."

Mr Abbott would not say who made the call or exactly what was said.

At 10:45am another media advisory arrived from Mr Abbott's office - the "picfac" (picture facility) had been moved to a meat wholesaler at Fyshwick.

Several journalists, including Channel 10's Hugh Riminton, were told by staffers from Mr Abbott's office that their cameramen risked being charged with trespass if they remained at The Butcher's Shop.

"Why did your staff make aggressive phone calls to media offices threatening them with trespass, saying they were in danger of the crime of trespass for being at the premises, when we'd been called there for a media alert?" Riminton asked.

"I have given you the explanation," Mr Abbott said.

Under the carbon pricing scheme, households will get tax cuts and entitlement boosts to offset higher power and other costs.

Australia's 500 highest-polluting companies will pay $23 for every tonne of carbon pollution they emit from July 1 next year.

The Opposition says it is no foregone conclusion that the bill will pass the House of Representatives, saying one or more Labor members might cross the floor to defeat it.