The government has been urged to publish the report in its 2014 plain packaging consultation “without further delay” as well as regulations on the forthcoming legislation.

Nick de Bois, Conservative MP for Enfield North, said: “If the consultation process is not to be dismissed as a sham then the government must publish the responses promptly.

“Now that ministers have confirmed they wish to press ahead with standardised packaging it’s frankly ludicrous not to publish their own report on the consultation, however inconvenient that may be for them.”

Simon Clark, director of Forest which runs the Hands off our Packs campaign, said: “We submitted 53,000 letters and 97,000 petition responses to the consultation.

“That was almost six months ago. The closing date was in August yet the government still hasn’t published a report, nor has it revealed how many consultation responses were received in total. 

“For the sake of transparency we urge the government to publish that information without further delay.”

Leicester retailer Raj Aggarwal urged the government to publish the plain packaging regulations as soon as possible.

“MPs need to have had time to digest the regulations, and to talk to retailers about their impact on stores and the wider industry, prior to the free vote,” he said.