Cabinet secretary Francis Maude’s move is the centrepiece of a big shake-up of procurement designed to make it easier and faster to bid for Government work.

Potential contracts with a value of more than £50bn are due to be published today in a first wave of work mainly based on IT and facilities management.

Construction contractors will need to wait until April for major building and infrastructure projects to be advertised.

The reforms are also being framed to open up more work to smaller firms.

Maude will say that under the new plans it would be 40% faster to do business with Whitehall as potential opportunities for private companies are flagged up earlier and procurement chiefs are told to speed up tendering.

The Government will change its culture in Whitehall to adopt an open door policy with suppliers to discuss future contracts.

Departments will also be told to break up some major contracts to make it easier for small and medium-sized enterprises to bid for the work.

The Government has set a target to complete all but the most complex procurement processes within four months from January next year. At present big Government procurement takes more than seven months on average.

Maude will aslo create a commissioning academy to train public sector procurement chiefs in how to be “confident and courageous” when awarding contracts.

He told the BBC’s Andrew Marr programme on Sunday that taxpayers were not getting value for money under the current system.

He said: “The public sector in this country spends a huge amount of money in buying in goods and services from outside, something like £230bn a year, and we don’t do it very well, frankly.

“We follow the European law extremely literally, and they have very legalistic processes. We have very big contracts, and we get the worst of both worlds at the moment.

“We don’t buy very well, we exclude a lot of competitive, innovative suppliers who will tend to be UK-based, so neither do we get good value for the taxpayer, neither do we spend the money particularly well, nor do we actually support UK businesses.”

The Cabinet secretary will travel to Brussels today to press for EU rules over government procurement to be simplified.