Restaurants and pubs have been urged to stop "dragging their heels" and sign up to salt reduction targets.
Councils said just one restaurant group, Jamie's Italian, and one fast food chain, Subway, had committed to the scheme since its launch five months ago.
The Department of Health voluntary targets aimed at cutting salt from the 10 most popular high street dishes including chips, burgers, pizzas and curries.
The Local Government Association claim some restaurant and pub meals contained up to 9g of salt despite current guidelines recommending adults consume no more than 6g of salt a day.
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The annual event has earned a place in the record books ahead of the grand final of the 60th anniversary show in Austria this evening.
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Some students argued that the centuries-old tradition of wearing gowns, suits and mortarboards to exams was 'archaic' and looked elitist.