All scheduled racing in Britain on 10 September will be cancelled and the sport will, in effect, go on strike, as racing escalates its protests against a Treasury proposal to align the rate of duty charged on sports betting with the rate for much more addictive games of pure chance such as roulette and online slot machines.

The move to abandon meetings at Uttoxeter, Lingfield, Kempton and Carlisle is expected to result in the loss of about £700,000 to the industry.

The action, first reported by the Times, has been agreed following cooperation between Jockey Club Racecourses, which operates Kempton and Carlisle; Arena Racing Company, the operator of Uttoxeter and Lingfield; and the British Horseracing Authority, the sport’s ruling body.

Gambling on games of chance is taxed at 21% of an operator’s gross profits, while the duty on betting – on racing, sports and other events without a fixed profit margin for the operator – is set at 15%. There is an additional charge of 10% of gross profits for bets on UK racing for the statutory Levy, which has returned money to racing since off-course betting was legalised in the early 1960s.

The proposal to equalise the duty rate for betting and gaming products was initially floated by the Treasury in the final months of Rishi Sunak’s Conservative government, but it survived the transition to a Labour administration and was the subject of a consultation process which closed in July.

Betting and gaming have been treated separately for taxation purposes since the Betting and Gaming Act came into force in 1961. There is a widespread belief in racing that a levelling of the duty rates will make the sport more expensive for gambling operators and as a result, far less attractive when compared with gaming products with a guaranteed return.

Alternatives for the tax regime around gambling include a proposal from the Social Market Foundation thinktank that gaming duty could be increased to 50% and sports betting to 25%, with changes to the Levy system ensuring that racing would not lose out.

The former prime minister Gordon Brown has also advocated for a significant rise in the duty charged on fixed-margin gaming products.

Launching the British Horseracing Authority’s campaign against the tax proposals last month, Brant Dunshea, the BHA’s acting chief executive, said the sport’s stakeholders were “united in their opposition to the Treasury’s proposals to harmonise remote gambling duties”. Dunshea added: “If the chancellor delivers this tax bombshell at the autumn budget, not only will jobs be lost but the future of Britain’s second-largest spectator sport will be in jeopardy.

“This is why it is vital that the government carefully considers the argument made by all British racing’s stakeholders and works alongside us to protect a cherished national institution.” The races lost on 10 September are expected to be added to other cards scheduled around the same time.

The date chosen for the racing “strike” is 24 hours before the start of the high-profile St Leger meeting at Doncaster, which the prime minister, Sir Keir Starmer, and his wife, Victoria, a keen racing fan, attended last year.