Government CTO Liam Maxwell has said he will be answerable for whatever replaces HM Revenue & Customs' (HMRC) 'Aspire' ICT outsourcing deal when it expires in June 2017.
Appearing in front of MPs on the Public Accounts Committee (PAC) yesterday, Maxwell said that the Cabinet Office was working to help HMRC to bring control of its ICT back in house and split the deal into number of smaller, more manageable contracts.
Under questioning by PAC chair Margaret Hodge he said: "If it goes wrong, I am accountable".
Aspire is the biggest ICT deal in Whitehall, with prime contractor Capgemini receiving an average of £813 million a year since it was set up in 2004, according to a National Audit Office report in July.
By the time the deal ends in 2017, it will have cost £10.4 billion, the NAO said.
Maxwell told MPs that he had not seen the full business case for the Aspire replacement programme yet but expected to, "before Christmas".
He added: "From what we've seen so far, we're confident they've taken the right approach and understand the risks."
However Maxwell said that the Cabinet Office would be prepared to agree to extend the contract if it was unconvinced by the work done to replace it.
He said: "If HMRC said 'we've had a go and the only option is to extend the contract', if there was a reasonable and strong case to do so, we could extend it.
"I think if the business case appeared in December and it was an unconvincing piece of work, we would have an idea of whether we need to extend then. We should know for sure by March next year."
HMRC to save £200 million a year
In a PAC session earlier this week, HMRC's chief digital and information officer Mark Dearnley said that the department expects to save at least 25% a year on its current IT costs, equivalent to £200 million a year, when the contract expires.
Much of the £200 million in savings will come from migrating hosting to the cloud, allowing the department to buy capacity that can scale more closely to peaks, such as tax return deadlines, and troughs in demand, Dearnley explained.
HMRC has one of the biggest ICT estates in government. It has six major data centres and is responsible for 1.1 billion transactions every year.
However Hodge warned that the process of replacing Aspire may put some of the £500 billion in tax currently collected via Aspire at risk.
MPs also raised concerns over whether HMRC has the requisite in-house capability to manage the transition to the new set up, with just 95 employees working on Aspire in the department day-to-day.
The NAO report in July warned that HMRC is "running out of time" and "must now act quickly" to take control of its ICT operations and plan for the mega-contract to be replaced with a larger number of contracts with a wider pool of suppliers.
A report by the Institute for Government and Spend Network published in June found that 82% of Capgemini's revenue from Whitehall came from the Aspire contract alone.