The Labour Party’s other election – for its London mayoral nomination – saw Tooting MP Sadiq Khan turn this week to a favourite football of politicians across the country: the NHS.

The former Shadow Justice Secretary claimed that millions of pounds could be freed to pay for more frontline hospital staff if costly private finance (PFI) construction contracts were bought out.

PFI deals, controversial because of their high rates of interest, have seen private companies profit hugely after building hospitals and running other Government projects.

Kingston Hospital’s 29-year, £33.1m PFI deals were signed in 2007 and 2008. Last year all payments, including service charges, took up 6 per cent of operating revenues.

However, the hospital said, service charges made up three-quarters of that figure.

The hospital’s projected £8.8m deficit for 2015 to 2016 is not predicted to affect repayments, a spokeswoman added.

Mr Khan touted a paper by the NHS Support Federation, which has provided research for Labour in the past and campaigns against “market forces” in the health service, and said cash-strapped councils could even invest their pension funds in new “Bevan” bonds to buy out the contracts.

He added: “We need innovative ideas and solutions to ensure our hospitals can keep wards open, maintain A&E services and continue to deliver the high quality patient care Londoners deserve.

“Bonds are one way of potentially doing that, as is renegotiating some of these existing PFI contracts, which have become a millstone around the necks of our hospitals.”

North Kingston MP Zac Goldsmith, who is part of the Conservative London mayoral race, was not available for comment.