Deputy Prime Minister Wayne Swan calls on opposition leader Tony Abbott to convince his 'friends' in big tobacco companies to halt their ad campaigns against the federal government's plain cigarette packaging measure.

Mr Swan said that it doesn't matter now if Mr Abbott or any of his party colleagues were directly involved in the move or not as he argued that the opposition leader must put forward a clear stand on the issue and "if he hasn't made any commitments, then he should call on big tobacco to cease this campaign."

The Labor-led government announced in April that tobacco companies would be required to sell cigarette packs in plain packaging and the directive would be implemented by the middle part of 2012.

However, giant tobacco firms raised a howl and vowed to bring the issue to the courts and recent reports signified that they may be starting their offensive against the proposed restriction as it was revealed that cigarette makers were bankrolling the $5 million advertising campaign launched by a retailers' association.

Also, New Ltd published a new item on Wednesday pointing to Liberal Party strategists as contributors in framing the campaign strategy but Mr Abbott countered on the same day that he and his party were not in collusion to any sort of 'pro-smoking campaign'.

In spite of the Liberal's vehement denials, Mr Swan insisted that the opposition party must answer the questions raised by the issue as he urged Mr Abbott to clarify the extent of his involvement in the campaign.

Mr Swan added that the opposition leader would be able to clear the air once the public is informed on the depth of his party's involvement in a matter explicitly supported by giant tobacco firms opposed to a government policy.