Instead, the industry is set to call for a new code to be supervised by the Electoral Commission, which has launched a review of the current unregulated system for party political campaigns.
The commission oversees elections in Britain but may be reluctant to be drawn into the day-to-day battles between the parties during the heat of a general election.
But senior advertising figures believe it would be wrong to set up a new body to police a new political code or to return political ads to the remit of the ASA.
Andrew Brown, the chairman of the Committee on Advertising Practice and director-general of the Advertising Association, this week welcomed the commission's review and said the committee would assist the parties to draw up their own code.
He said the key questions to be resolved included whether the parties would accept the authority of a new adjudicating body.
Political advertising was subject to part, but not all, of the code until 1999. But the "half in, half out" system was ended amid confusion after the ASA ruled against the Tories' "demon eyes" ad depicting Tony Blair but was unable to adjudicate on Labour's "Same old Tories, same old lies" poster.