Ads slammed by ASA to face ban from awards ceremonies.(Advertising Standards Authority )

The Committee of Advertising Practice issues guidelines to prevent what it terms 'offside goals'.

Watchdogs are renewing their warning to industry awards organisers not to accept entries that have fallen foul of the Advertising Standards Authority.

And in an effort to curb illegal advertising activity, they are calling for the rejection of entries that have included flyposting even if a flyposter is not part of the campaign that is submitted.

The Committee of Advertising Practice, which has issued the warning, admits it has no sanctions against organisers who choose to ignore it. But Andrew Brown, the CAP chairman, said: 'The ad industry supports self-regulation, so we would expect those running awards to conform to the rules.'

The initiative comes as the war against flyposting escalates. The Outdoor Advertising Association has hired a company to photograph flyposting activity in London.

Some industry leaders have argued that it is often difficult to pinpoint the source of a flyposting campaign. But Brown said: 'It seems pretty unlikely that an advertiser can claim no knowledge of flyposting carried out in its name.'

The CAP says it has no evidence that awards organisers are flouting the rules, but was anxious to stop what it called 'offside goals'.