The House of Lords gave an unopposed second reading to the Television Advertising (Food) Bill last Friday, but it is unlikely to secure enough debating time to complete its passage through Parliament.
Richard Watts, the campaign co-ordinator of the Children's Food Campaign, said: "The momentum behind a 9pm watershed is growing all the time. Given that Gordon Brown has already signalled his support for controls on junk-food ads before the watershed, we're very confident that this public health measure will become law."
But Labour peer Baroness Thornton, who proposed the Private Member's Bill, admitted it was unlikely to reach the statute book because the Government and Opposition front benches opposed it.
Baroness Peta Buscombe, the chief executive of the Advertising Association, attacked the "bizarre posturing" of pressure groups and "C-list celebrities" who had jumped on the bandwagon.
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