The outgoing chairman of the Public Accounts Committee has lambasted the state of public sector IT procurement, insisting serious weaknesses must be fixed if the government is to achieve its much-trumpeted multibillion pound efficiency savings.

Edward Leigh singled out IT procurement as “particularly weak”. He said: “Projects are over-ambitious, overly complex and fail to deliver what is promised while costs rocket.”

In an open letter to his successor, who will be appointed shortly after the country’s general election, Leigh said better IT procurement would help find savings that are “easily available”, without taking steps that risk “threatening” front line services. Other steps included reducing bureaucracy and complexity, improving front line services, core management skills and the analysis of information.

In a damning note on government operations, Leigh said the government needed to start learning from its experiences, and reminded ministers that public scrutiny of their work “must be taken seriously”.

There were a number of major problems that were examples of the government’s failures in IT procurement, he said. These included the “woeful” £350 million system implementation at the Rural Payments Agency, run by Accenture, in which the Agency’s “poor leadership” meant data had become full of errors and the system was at risk of becoming obsolete.

The Ministry of Defence’s near-£8 billion Defence Information Infrastructure communications system, being set up by HP-EDS, was also criticised for its poor planning, with “no proper pilot” and an underestimation of the difficulty of implementing the project.

Additionally, simple IT running costs were too high, he said. Some £813 million could be saved if the Department of Communities and Local Government, Defra, the DWP and HM Revenue & Customs brought IT running costs per staff member down to the level of the Ministry of Justice’s costs.

Leigh was also critical of the government’s lack of clarity over shared services, with the Cabinet Office claiming £1.4 billion could be saved each year across government. This was being aimed at “without accurate information on what corporate services cost and how they perform”, as well as no timetable for the savings, he said.

A shared services scheme at the Department for Transport, with IBM, had failed on cost, he said. It was aimed at saving £57 million by 2015, but “now looks like the taxpayer will have to stump up £81 million to pay for it”. The system was not properly tested and the department failed to garner staff support for it.

Leigh said there were also a number of good examples of best practice, including the Department for Work and Pensions’ Payment Modernisation Programme. But only a few programmes drew on such examples, and in most instances departments did not carry out final Gateway reviews to determine if their programmes delivered the planned benefits.

Successful IT projects required senior level engagement, the government acting as an intelligent customer, and ensuring the promised benefits could realistically be delivered, he said.

"We have been impressed by some talented people who know what they are doing and are determined to do it well, but more frequently we have been shocked by the failure to apply basic management disciplines to major projects and programmes,” Leigh said.

While PAC recommendations had helped save over £4 billion, it was “disappointing” to see the same problems reoccurring on projects, he said.

It was time for departments to “stand up to ministers”, he said, if they were under undue pressure or asked to “deliver the impossible”.