People buying a takeaway coffee are among those required by law to wear a face covering from Friday, but some high street chains said they will not penalise customers who fail to do so.

Police can hand out £100 fines to people in shops, shopping centres, banks, takeaway outlets, post offices, sandwich shops and supermarkets who flout the rules, but the College of Policing has said officers “should only be required as a last resort”.

Guidance issued by the Government on Thursday for England confirmed face coverings in takeaways would be mandatory, after weeks of confusion and varied messaging from ministers.

It states that staff in premises where face coverings are required are encouraged to “take reasonable steps to promote compliance with the law” and can refuse entry to people who do not have a valid exemption under the rules.

Retail and trade organisations criticised the Government for taking so long to publish the new laws and guidance, having announced the measure more than a week ago, while union leaders voiced fears the rules could put workers’ safety at risk if there are abusive customers or people who refuse to wear a mask.

Costa Coffee said it would “not be challenging customers” who are not wearing a mask “since they may have a legitimate reason as to why they are unable to wear one”.

Sainsbury’s said while it is asking everyone to continue “playing their part” in helping to keep everyone safe in store by following the rules, “our colleagues will not be responsible for enforcing them”.

Asda said it will “strongly encourage customers to wear a face covering”, but added: “It is the responsibility of the relevant authorities to police and enforce the new rules.”

Tesco will be selling face coverings at the entrance and Waitrose said staff would be at the entrance to stores reminding customers of the requirement.

Customers will be “required” to wear a face covering in Greggs.

McDonald’s said takeaway customers will need to wear face coverings but those who eat in the restaurant will not unless they are moving around the premises, for example to use toilets or when at self-order screens.

The British Retail Consortium called on customers to be “respectful” of the new rules and criticised the length of time taken for the guidance to be published.

UKHospitality chief executive Kate Nicholls said takeaway outlets had been left with “a very short time to properly brief staff, prepare signage and take steps to encourage compliance”.

The British Medical Association said while the guidance is helpful, it has come late in the day.

Dr Chaand Nagpaul, the association’s council chairman, said the measures were “long overdue” and added “the uncertainty of recent weeks has done nothing to inspire public confidence”.

Venues like restaurants, pubs, gyms, hairdressers, beauty salons, leisure centres, cinemas, concert halls and theatres are exempt from the new rules.

Dr Nagpaul warned the virus “does not discriminate between buildings” and said there must be “an absolute assurance” that other mitigating measures are in place at those sites, such as screens and physical distancing.

Other exemptions to face coverings include children under 11, people with breathing problems and anyone who cannot put on, wear or remove a face covering because of a physical or mental illness or impairment or disability.

The guidance states that people should “assume” it is standard to wear a face covering when visiting a hospital, GP, care home or other primary or community healthcare setting.

Last week police chiefs were blindsided by the Government’s announcement after they were not told in advance of the plans and some police chiefs warned there are not the resources to patrol the aisles.

The Police Federation of England and Wales, which represents rank-and-file officers, said it was “unrealistic and unfair” to expect them to patrol the aisles looking for people breaking the coronavirus regulations.

Metropolitan Police Commissioner Dame Cressida Dick said she hoped shoppers who refuse to wear masks would be “shamed” into compliance.

The Government said the responsibility for wearing a face covering “sits with individuals”, adding: “Businesses are encouraged to take reasonable steps to encourage customers to follow the law, including through signs and providing other information in store.”

The Prime Minister’s official spokesman told reporters on Thursday: “With shops, we would expect them to give advice to customers and remind them that they should be wearing a face covering and I’m sure the overwhelming majority of the public will do so.”

The laws could be in place until at least January, and could even last a year, unless the Government decides to scrap them in the meantime.

Face coverings are already mandatory in shops in Scotland and will be compulsory in shops in Northern Ireland from August 1. There are no plans to make them compulsory in shops in Wales.