Labour ministers are under pressure to overturn the previous government’s “bizarre” decision not to impose stricter regulation on gambling advertising, particularly around sport, from politicians, campaigners and figures from the world of football.

At a summit held close to the Houses of Parliament in Westminster, a succession of experts called on the culture secretary, Lisa Nandy, to impose much stricter controls on how gambling is marketed, in order to protect children and vulnerable people.

Tony Blair’s government revised Britain’s gambling laws in 2005, removing restrictions on advertising just before the invention of the smartphone effectively put a casino in every pocket. Bookies and online casinos spent more than £1.5bn on advertising in 2017, a figure that is believed to have risen substantially since then.

Speaking at the event, former Conservative leader Iain Duncan Smith, who co-chairs a cross-party parliamentary group examining gambling harms, cited a survey by Survation showing that most of the public support banning gambling ads all together.

While he stopped short of advocating such a measure, he said: “Politicians need to find their way towards the public on this,” said Duncan Smith.

“It’s clear and obvious what can be done and what should be done.”

Duncan Smith called on the new government to outlaw incentives and inducements to gamble, such as “free” bets, and urged ministers to restrict gambling advertising in sport, banning sponsorship on football kits and betting ads in and around stadiums.

Premier League clubs have agreed to stop accepting betting sponsors on the front of their shirts by the end of next season but the voluntary measure will not affect the rest of the shirt, pitchside hoardings, or clubs further down the football pyramid.

Mark Palios, the former chief executive of the Football Association and chair of Tranmere Rovers, said: “Do they not think that children who support lower league clubs are as important as children who support Premier League clubs?”

Tranmere is among 40 football clubs that have signed up to The Big Step, a campaign to persuade football clubs to reject betting sponsors. In 2022, the Guardian revealed that English Football League clubs were taking a cut of gamblers’ losses, under the terms of a deal with SkyBet.

Several campaign groups also called for a pre-9pm ban on betting and casino advertising, a policy that has the backing of GambleAware, the UK’s leading gambling charity.

Figures released last month by the Gambling Commission, obtained using a new methodology, indicate that the number of people suffering harm from problem gambling may be eight times higher than previously thought, affecting up to 2.5% of adults in Great Britain.

Lord Foster, chair of Peers for Gambling Reform, which convened the summit, said the gambling act gave Nandy the power to address this by “acting quickly to reform gambling advertising, however she decides is appropriate”.

He said curbing gambling ads would not require primary legislation and would be easy to implement, given the government’s large majority.

The Liberal Democrat peer said it was “bizarre” that the previous government had not addressed gambling advertising in a white paper on regulatory reform, published last year.

The proposals did include measures such as a £5 cap on slot machine stakes and new affordability checks, which are being tested in a pilot scheme.

However, the Conservative government said it would not crack down on advertising due to a lack of evidence proving that it leads to gambling harm.

Dr Heather Wardle of the University of Glasgow, said it was not possible to prove beyond doubt that ads lead to problem gambling.

She pointed out that previous curbs on products such as tobacco had relied on observations of their impact and that the same could apply to gambling.

Football commentator Clive Tyldesley told the summit that he had left his job as a broadcaster with the radio station TalkSport because of its policy of promoting sports gambling during games.

Guy Parker, chief executive of the Advertising Standards Authority, said policymaking was for the government but admitted he had been shocked by the amount of gambling advertising he saw.

A spokesperson for the Betting & Gaming Council, an industry lobby group, said it had worked with sports teams on a new sponsorship code, leading to more promotion of safer gambling messages and efforts to limit appeal to children. The BGC also pointed to the “whistle to whistle” ban, under which firms agreed not to advertise during live sports programmes.

Studies have suggested that this measure is outweighed by the fact that betting logos can appear up to 3,500 times in the course of a single Premier League match due to other promotional methods, such as pitchside hoardings.

A government spokesperson said: “Most people gamble without issue, but we recognise the impact harmful gambling can have on individuals and their families and we are absolutely committed to strengthening protections for those at risk.”