Retailers that prepare and package food to sell on-site should list all ingredients they use to avoid allergy deaths, the Food Standards Agency (FSA) has said.
The FSA will advise ministers that food outlets should place labels on products, which include a full list of ingredients with all 14 major allergens highlighted.
The proposed changes follow the death of Natasha Ednan-Laperouse, who died after eating a sandwich from Pret A Manger.
Her parents, Nadim and Tanya Ednan-Laperouse, hailed the changes as "a momentous decision" and said the proposals could help to prevent similar tragedies.
In a statement Natasha's parents said: "We are delighted that the FSA has recognised what consumers are asking for, which is that full ingredient labelling across all pre-packaged food is implemented.
"Business must always listen to its consumers particularly in matters of life and death."
The FSA announcement follows ITV News' exclusive sitdown with Pret A Manger's boss last week in which he announced the firm was rolling out full labelling.
Currently, food prepared and sold on-site does not require warning labels about potential allergens because it is assumed that customers who require information will question staff.
The FSA board discussed options ranging from promoting best practice in the food industry to the mandatory labelling of allergens but decided to recommend that food outlets must label all food with a full list of ingredients, highlighting the 14 major allergens, including nuts, eggs and milk.
The Department for Environment, Food and Rural Affairs will have the final say over whether new rules are introduced.
FSA chairwoman Heather Hancock told BBC Radio 4’s World at One: “It did attract some opposition from business.
“From public sector bodies there was a concern about the resources to help business comply with this rule and then to enforce the rule.
“From businesses themselves… there is a level of misunderstanding about what we are actually talking about.
“We are not talking about every fresh sandwich being made in a sandwich shop, so I hope that slightly reduces their level of anxiety.
“But we are balancing consumer protection, public health protection with the ability of people to deliver a good business service and choice to people who have got an allergy or intolerance.
“So our discussion today was very nuanced but ultimately this is a huge quality of life, and life threatening, issue for a proportion of the population and that is what we have fallen in favour of.”
Miss Ednan-Laperouse, 15, from Fulham, south-west London, collapsed on board a flight in July 2016 after eating an artichoke, olive and tapenade baguette she had bought at a Pret outlet in Heathrow Airport.
The coroner at her inquest said she died of anaphylaxis after eating the sandwich containing sesame, to which she was allergic.
Pret A Manger started a national roll-out of full ingredient labels on freshly made products last week as part of its response to the death.
Pret has offered to share the details of the labelling roll-out with the Government and wider industry to help other food businesses adopt a similar approach.