Rebecca Long Bailey, the Labour leadership candidate, has refused to deny that she worked on private finance initiative (PFI) contracts within the NHS while she was a corporate lawyer, despite campaigning to abolish them as a politician.

Long Bailey’s closest ally, John McDonnell, vowed to scrap PFIs and nationalise private contracts if Labour got into government, describing them as a “scandal”.

The Salford and Eccles MP has repeatedly spoken out against “rip-off” private finance deals in the NHS and once wrote that she became a lawyer “for the NHS” to “give something back and protect our NHS bodies from harm”.

However, The Sunday Times has learnt that Long Bailey worked directly under a leading expert in PFIs during her career at Hill Dickinson, a commercial