Government cuts will be “devastating” to grassroots sport and will banish the legacy of the London 2012 Olympics, according to shadow home secretary Andy Burnham.

Speaking at yesterday’s Substance National Conference – titled Sport for Development: A Whole New Ball Game? – Burnham warned that a decrease in the sports spending, particularly at local authority level, would be the “final nail in the coffin” for the legacy created by the last Games.

A Comprehensive Spending Review, which is due to be delivered by chancellor George Osborne on 25 November, is expected to reveal cuts of up to 40 per cent for the Department of Culture, Media and Sport (DCMS).

The budget of Sport England, the public body which oversees grassroots sport, is partially protected by the fact that most of its funding comes from the National Lottery.

According to its 2014/15 annual report, Sport England’s funding was split 75/25 between the National Lottery and the Exchequer. Over the 12-month period, the body received £83m (€119m, $127m) in funding from the government, down on 2013/14’s figure of £88.6m (€127m, $136m), while the National Lottery accounted for £243m (€347m, $372m).

However, the former Labour leadership candidate said the sports sector needed to brace itself for cuts to local authority budgets, which are expected to be slashed by up to 40 per cent.

Cuts of up to 40 per cent to some local authority budgets since 2010 have already hit funding for facilities and sports programmes across the country, as sport and recreation is one of the few discretionary spending areas.

Burnham said sport and recreation was an “orphan policy” that “nobody wants to know and nobody wants to take responsibility” for.

“These cuts will be devastating for sport,” he added. “Whitehall doesn’t prioritise sport and physical activity. Within the individual departments, not one of them see it as one of their main responsibilities.”

The Sport and Recreation Alliance launched a campaign lobbying Osborne to protect grassroots sport. The #GetYourKitOn initiative, established last week, has enabled 1,200 emails to be sent to the Treasury to demand the protection of funding.

A poll carried out by the umbrella organisation found that 79 per cent of people felt the government should be doing more for grassroots sport, while 75 per cent believe that it should receive more funding from the Exchequer.

Following the chancellor’s review next week, sport minister Tracey Crouch will publish her strategy for sport, which will clarify the way in which the government will fund sports governing bodies in the future.

Earlier this week, her cabinet colleague, business secretary Sajid Javid, called on the private sector to play a “massive role” in increasing sporting participation.