Exclusive: Resolution could pave way for full return to frontline politics, but allies stress she has no plans to directly challenge Keir Starmer

For months there has been an apparently insurmountable obstacle to Angela Rayner going for the Labour leadership, should Keir Starmer find himself facing a contest.

The investigation by HMRC into the former deputy prime minister’s tax affairs has hung heavily over her since she was forced to resign last September over underpayment of stamp duty on her seaside flat.

But now Rayner’s allies are increasingly confident that the inquiry will be resolved before the May local elections – a moment of high peril for the prime minister – paving her way for a full return to frontline politics.

The Guardian understands that outstanding legal issues over the tax investigation are being ironed out by lawyers and the HMRC process is now approaching its conclusion.