US private equity giant Apollo Management should rebid for the embattled rail firm FirstGroup because the company needs a “fresh face at the helm”, one investor has said.

FirstGroup revealed last month it had rejected an offer from Apollo, which it claimed “fundamentally undervalues” the company.

The details of the approach were not disclosed but an investor has now called on Apollo to make a bid before the May 9 deadline after which there would be a six-month moratorium on any offers.

“I do think the management team is under pressure,” the investor, who asked not to be identified, said. “Tim O’Toole [the current chief executive of FirstGroup] has been there a long time and not much seems to be happening so I think it does need a fresh face at the helm.”