Sky News has learnt that Andy Milner, who left the Spanish-owned company in 2019, is in advanced talks with Buckthorn Partners, a private investment firm, about retaking the top job at Amey.

Sources close to the situation said a deal could be finalised between a Buckthorn-led consortium and Ferrovial, Amey's current owner, as soon as this month.

Mr Milner spent four years as Amey's chief executive, and has more recently been executive chairman of Matrix Networks, which installs utility infrastructure for corporate customers.

If confirmed, his return to the company would coincide with its purchase by an investor group which includes Lord Philip Hammond, the former chancellor, who is a partner at Buckthorn.

In June, Sky News revealed that a consortium comprising Buckthorn and One Equity Partners, a US-based private equity firm, had entered exclusive talks to buy Amey.

The outsourcer, which has endured a string of contractual and financial difficulties, was put up for sale for a second time last year by Ferrovial.

The Spanish infrastructure giant had previously aborted an auction process which began in 2018.

New leadership at the company would represent a further changing of the guard in the sector after Serco announced the retirement of its long-serving boss, Rupert Soames.

A takeover by Buckthorn and One Equity would see one of the UK's biggest private sector employers changing hands.

Amey, which ranks among the government's most significant private sector contractors, has a workforce of roughly 15,000 people.

Among the public sector activities it refers to on its website are the maintenance of the UK defence estate, keeping 60 prisons "safe and compliant" during the COVID-19 pandemic, and developing the power programme for the HS2 high-speed rail link.

Buckthorn describes itself as a private investment firm predominantly focused on acquiring assets in the energy sector.

Its portfolio includes Ashtead Technology, which makes advanced subsea tools, and Paradigm Energy Ventures, which it owns alongside an arm of Saudi Aramco.

In addition to Lord Hammond, the Buckthorn partnership includes Lord Colin Moynihan, who served as sports minister under Margaret Thatcher.

The two men were university contemporaries, and Lord Hammond chaired Lord Moynihan's constituency Conservative Association when the latter was an MP during the 1980s.

Lord Hammond was the MP for Runnymede and Weybridge for more than two decades before losing the party whip when he opposed government policy by voting against Britain leaving the European Union without a deal.

He spent nearly a decade in the Cabinet, including as chancellor, foreign secretary and defence secretary.

Since quitting politics, he has amassed an array of directorships and advisory posts, including in the fintech, transport and real estate sectors.

Ferrovial, which owns a big chunk of London Heathrow Airport, has contemplated a sale of its entire global services business for some time.

The initial attempt to divest Amey in the UK was unsuccessful amid uncertainty about the future of a controversial £2.7bn roads contract in Birmingham.

A dispute with the city's local authority was resolved in 2019, although Amey only finally extricated itself from the deal last year.

The tidying-up of Amey's business is likely to provide prospective buyers with a clearer view about the company's valuation in a sector which has been rocked by several prominent corporate collapses in recent years, including that of Carillion and Interserve.

Morgan Stanley is handling the auction of Amey.

A spokeswoman for Buckthorn declined to comment.