A report on the future of Network Rail (NR) has dismissed privatisation of the company.

But the Government-commissioned review, carried out by Nicola Shaw, does recommend the introduction of private sector capital to parts of the network.

It also called for devolution of regional routes in a bid to create more flexibility to meet the needs of passengers and freight companies.

The Government welcomed the report and pledged to "respond in full later this year".

In a foreword, Ms Shaw explained that the review focused on the "core areas" of customers, devolution and growth, but added: "The rail network is complex... there aren't any silver bullets here just waiting to be found and used."

She insisted her recommendations will help lead to a "cost-efficient rail system".

On the issue of how NR should be financed, the review stated: "The report team has dismissed privatisation of the whole company."

NR chief executive Mark Carne said he endorsed Ms Shaw's "desire to see more private finance coming into the railways".

He added: "We have been successful with this in the past and I consider that more private money and funding from the people who will benefit from railway improvements is a sensible way to deliver a bigger and better railway."

NR admitted in October that the cost of electrifying the Great Western line between London and South Wales could reach £2.8 billion despite an estimate of £874 million being given in January 2013.

Meanwhile electrification schemes for the Midland Main Line and the TransPennine routes have been delayed.

Stephen Joseph, chief executive of Campaign for Better Transport, said the review should "mark a positive end to a difficult" 12 months for NR.

He urged the Government to implement its findings while resisting further fragmentation of the company.

Mick Whelan, general secretary of train drivers' union Aslef, claimed the timing of the publication of Ms Shaw's report - shortly after Chancellor George Osborne's Budget - was chosen "in the hope nobody would notice".

He said: "What a waste of time and money this has been."

Manuel Cortes, leader of the Transport Salaried Staffs Association, warned that the review will not stop NR's plans to "flog off station concourses, land or even its strategic electric grid".

He added: "Selling our stations to foreign investment funds will allow them to ship abroad lucrative profits made at our expense."

Office of Rail and Road chief executive Joanna Whittington claimed the Shaw Report has set "an ambitious agenda" which will "benefit the whole of the railway".