THE operators of Scotland's railway network will appointment a new chief within days following the announcement beleaguered boss Phil Verster was to quit the operation.

Mr Verster has been at the helm of the ScotRail Alliance for barely 18 months but is to leave his post as managing director around March.

His departure from the £260,000-a-year job follows a turbulent period for the company, which has faced calls to be stripped of its £7 billion 10-year franchise to run Scotland's railways for poor performance.

He has been at the centre of a bruising rows over the performance of the country's railways in the past year, with the network hit by the impact of the programme to modernise it as well as several high-profile incidents leading to major delays.

He will head up the construction of a new line between Oxford and Cambridge with operator East West Rail.

Mr Verster is expected to be succeeded by Alex Hynes, managing director of Northern, which runs trains in the north of England, industry sources have said.

Steve Montgomery, Mr Verster's predecessor as head of ScotRail has been tipped for a potential return to the job. Insiders however have appeared to rule out another return to Scotland's top railways job by Mary Grant, currently head of National Express.

ScotRail Alliance issued a statement yesterday afternoon stating that "Phil’s successor has been agreed and will be announced in the coming days".

Mr Verster is understood to have expressed surprise in private at what he believed to be the over-politicisation of the rail industry in Scotland in recent years.

Commenting on the resignation, Scottish Labour leader Kezia Dugdale said passengers were "fed up with delayed, overcrowded and cancelled trains" and claimed the relationship between the SNP and ScotRail had "broken down".

She added: "One man has walked, and the only man left standing is (transport minister) Humza Yousaf.

"He must address this ScotRail crisis and explain to passengers when they will see improvements. The clock is ticking."

The Scottish Liberal Democrats have also called for Mr Yousaf to give a statement to Parliament over the resignation.

The party's transport spokesman Mike Rumbles referred to the South African's appearance before a Holyrood committee on Wednesday where doubts were raised over the Scottish Government plans to give a week's free train travel to ScotRail yearly and monthly season ticket holders.

He said: "We were all astonished by the fact that the transport minister had not even got agreement from Mr Verster over the spend of £1.8 million to pay for a week's free travel when those funds had already been earmarked for rail improvement services.

"It is obvious to me that Mr Verster was under incredible pressure when he couldn't answer in detail questions the committee was asking him

Mark Carne, chief executive of Network Rail, one of the ScotRail Alliance partners, said: "Phil has done a great job setting up the ScotRail Alliance and overseeing the delivery of one of the largest programmes of rail modernisation in Scotland since Victorian times.

" I am delighted that a leader of Phil’s calibre will be heading up the new East West rail project, recently announced by the Secretary of State. We have agreed a replacement to succeed Phil and will be making an announcement shortly.”

Dominic Booth, managing director of Abellio UK, the Dutch firm which operates the ScotRail franchise, said: “Phil has played a key role in helping us create the ScotRail Alliance, the first time an operating company has come together in such a deep alliance with Network Rail to deliver the very best for our customers. We are currently investing in a fleet of 70 new trains, which will transform the rail travel experience of our customers.”

A Scottish Government spokesman said: “We are grateful to Phil Verster for his hard work during a transitional time in charge of Abellio ScotRail and the ScotRail Alliance and wish him well in his next venture. He has overseen many improvements and considerable investment which will ultimately lead to major benefits for passengers."