"The Cabinet Office and the Government Procurement Service will need to work with departments to address these problems, and build shared plans, including much more stretching targets for centralised expenditure and ICT savings," it said.
The PAC also criticised the government for not changing its procurement practices to support its commitment to SMEs.
"The government has a long way to go in its aspiration to achieve 25 percent of its procurement spending with small businesses by 2015," it said.
"Current data suggests that, despite clear commitments, only 10 percent of government spending is currently with SMEs. However, there are also major gaps in SME data, which means that it is not possible to confirm this figure."
Earlier this week, the Cabinet Office announced new procurement rules for the whole of the public sector that aim to make it easier for SMEs to win business with government.
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