Pizza Hut has been criticised for running a “dangerous” promotion that offered customers “free spins” at online casinos with their takeaway.

Online pizza orders were accompanied by a message congratulating customers for having “unlocked up to 300 free spins at your favourite casino”.

The message continued: “No deposit required! Claim your spins today!”

Online casino games are associated with significantly higher rates of addiction than most other forms of gambling, according to multiple studies. The government recently acted to limit maximum stakes on such games to £5, or £2 for under-25s, a measure that will take effect next year.

The Pizza Hut promotion drew fury from campaigners including the former leader of the Conservative party, Iain Duncan Smith, and Annie Ashton, whose husband, Luke, took his own life after battling a gambling addiction partly fuelled by “free” bets.

Ashton said: “The recklessness of this Pizza Hut promotion is staggering – offering hundreds of free spins on highly addictive casino games while not knowing if those people may be in recovery from an addiction is not just careless, it’s dangerous.

“Free spins can quickly lead to addiction to anyone spinning so many times. Pizza Hut need to end this promotion as soon as possible before any lives are lost.”

Duncan Smith, who chairs a cross-party parliamentary group examining gambling harm, said the promotion indicated that the government needed to introduce tougher regulation of gambling advertising and marketing.

“This is yet further evidence of how out of control gambling adverting has become. It’s not even possible to order a pizza without online casino products being pushed on to people,” he said.

The Pizza Hut promotion, which is no longer available, is part of a commercial arrangement with the casino promotion brand Free Spins Loops, part of a business called Digital Adventures, which is in turn owned by a holding company, Quantum International Holdings.

A Digital Adventures spokesperson blamed third-party advertising networks for the promotion appearing on Pizza Hut’s website.

“These placements are controlled by an external programmatic network that has built-in 18+ age protection capabilities.

“The advert in question was live for a short period at the end of November before being proactively removed on 28 November and it has not been live since,” they said.

The spokesperson did not answer questions about whether Digital Adventures or Pizza Hut shared a slice of losses racked up by customers who clicked through to gambling sites.

Labour has brought forward two measures from the previous government’s white paper on gambling, including the digital slots stake limit and a £100m-a-year levy on the sector.

But the white paper did not suggest any new restrictions on gambling advertising and Labour has yet to comment on its plans for regulating marketing.

The Guardian has approached Yum! Brands, which owns Pizza Hut, for comment.