Liberals frontbencher Jeremy Hanson used parliamentary privilege yesterday to allege that Mr Rattenbury, a Greens MLA, "hooked into" the Opposition Leader last week with a foul-mouthed attack on Mr Seselja as the two men continued their feud over the Greens' approach to direct action by protest groups.

Mr Rattenbury denied the accusation yesterday, saying members should be free to have forthright and private conversations with each other.

"We certainly had a robust conversation," Mr Rattenbury said.

"I think I might have used one expletive in the conversation. People swear in private conversations all the time. I completely reject the accusation of an expletive-laden tirade."

Mr Seselja has been trying to pursue Mr Rattenbury since last year, when Greenpeace attacked and destroyed experimental genetically modified crop in Belconnen, with the Liberals' leader alleging the Speaker refused to condemn acts of property damage by activists.

The Opposition Leader was on the attack again last week accusing Mr Rattenbury of failing to condemn last week's action against the Pace Farms battery hen operation in West Belconnen, believed to be the work of animal rights activists.

Mr Seselja's law and order spokesman, Jeremy Hanson, speaking under the protection of parliamentary privilege yesterday, accused Mr Rattenbury and his Greens colleagues of sympathising with protesters who cause criminal damage.

Mr Hanson alleged that his leader had been abused after holding a press conference criticising the Greens.

"I'm informed that Mr Rattenbury actually hooked into Mr Seselja after Mr Seselja did that media, after he made those media statements," Mr Hanson said.

Mr Hanson said Mr Rattenbury approached the Opposition Leader in the Assembly's courtyard with an "expletive-laden tirade at Mr Seselja and I can't use the language in this place, it would certainly be ruled unparliamentary".

"But it was abusive language, used by Mr Rattenbury, directed at Mr Seselja for making this point," Mr Hanson said. The Liberal frontbencher went on to accuse the Greens of hypocrisy.

"When Mr Seselja has the temerity to point out that hypocrisy, Mr Rattenbury attacks Mr Seselja, abuses him in most vile fashion," Mr Hanson said.