Current mental health spending would likely need to double to take the number of people with mental health problems receiving NHS treatment from 40% to 70%, according to a new funding report.

Securing the Future: funding health and social care to the 2030s – a report commissioned by the NHS Confederation – states UK spending on healthcare will have to rise by an average 3.3% a year over the next 15 years just to maintain provision at current levels, and by at least 4% a year if services are to be improved.

The report, written by the Institute for Fiscal Studies and Health Foundation, also put forward a model under which 70% of people with mental health problems receive treatment, which would need mental health funding levels to more than double to £32billion a year by 2033-34 – from 9% of the health budget to around 12%.

The IFS and Health Foundation concluded that in order to fund a modernised NHS, including this mental health standard, a funding rise of at least 4% per year for the next 15 years could be necessary.

Sean Duggan, chief executive of the Mental Health Network, which is part of the NHS Confederation, said: “It is well publicised we are seeing a rise in the number of people needing treatment for mental health issues and it was a welcome step for the government to state its intention to put mental health on equal standing with physical health.

“But if we are to really take mental health seriously and not fail thousands of people in need of help then one thing is crystal clear – investment must be found.

“Nobody wants to pay more than they have to – and all services, including mental health services, must continue to strive to be as efficient as they can be – but this is about protecting our health and ensuring people experiencing mental health problems are not left without proper treatment and support.”