Staffordshire Police have urged bars not to run drinks promotions that break a voluntary code on deals, which was withdrawn last year.
This follows the emergence of new promotions in Stafford, including the return of all-inclusive deals.
In a letter to venues, the police mention the British Beer & Pub Association's (BBPA) code on promotions. This was withdrawn over fears it broke EU competition laws. One section advises against all-inclusives.
The letter said the code "does contain some good advice, which you are encouraged to consider adopting in order to assist you to promote your licensing objectives".
"I encourage all who are running drinks promotions that are contrary to the guidance to review [it]."
The letter said if promotions "deemed irresponsible" cause problems, "enforcement action will ensue".
MA legal editor Peter Coulson said: "The very reason the BBPA code was withdrawn was because of concerns about interference with EU laws, and there is still the same danger in this proposal, whatever individual licensees might think."
Meanwhile, BII licensee of the year and Stafford host Chris Lewis has criticised the return of "irresponsible" drinks deals in the town.
"We have premises offering discounted drinks, happy hours and even 'all-you-can-drink-for-£10' offers.
"Promoting the rapid or vast consumption of alcohol only leads to problem customers and often results in drink-related crime."
3D Entertaiment boss: 'Everyone's happy with deals'
The boss of a nightclub company running an all-inclusive promotion in Stafford said police are happy with the deal.
3D Entertainment's Love2Love offers £10 all-inclusive on Tuesdays (students only) and Thursdays.
"Our operations manager met with police and they are happy with the way we are running the promotion," said 3D chief executive David Crabtree. "We have no complaints.
"We've got a very strong, detailed operating process behind any all-inclusive, which means entertainment, food, door entry, all included.
"We have very stringent measures about how much people can drink in any period of time.
"[The events] are running well. Customers like them because they pay a fixed price and that's all they pay."