While G-Cloud has seen a total spend of nearly £200m since its inception in 2012, recent think tank figures demonstrate that big IT suppliers remain the winners when it comes to public procurement.

The Government spent £4.3bn with the traditional big six IT firms last year, according to think tank Institute for Government.

Here’s who they are and how much they earned.

HP – £1.7bn

Hewlett Packard pulled in £1.7bn in each of the last two years to become the largest single recipient of Government money, according to the report.

But a think tank spokesman warned the figures were being reexamined after the Government disputed them.

The researchers initially believed 86% of HP’s public sector revenue came from a job centre contract with the Department for Work and Pensions (DWP), but the DWP told CBR the figure was "just wrong".

A spokesman added: "The correct figure is several hundred million a year to cover the majority of IT services and IT development used by DWP.

"This includes the IT platforms which are used for the processing of benefits and pensions."

Capgemini – £1.01bn

The French IT services firm also counted £997m from public sector contracts in 2012, found the think tank.

Fujitsu – £415m

IT infrastructure expert Fujitsu actually saw a £26m drop in earnings in 2013 compared to 2012. This is probably down to the Cabinet Office’s initiative, under Francis Maude, to break down big IT contracts into smaller ones served by SMBs.

The Home Office is due to switch to G-Cloud-sourced suppliers from 2016, when its Fujitsu contract expires, but the business and energy departments recently blamed small supplier integration issues in part for an IT ‘standstill’ after migrating from a Fujitsu system.

Atos – £401m

Atos is another outsourcing firm likely to suffer: its 2013 public sector revenue dropped £35m from the year before. Still, it raked in an average £35m a month over the two years.

IBM – £365m

IBM is still clinging on its top six spot, but it saw the highest drop in revenue across 2012/13 – from £459m to £365m.

CSC – £306m

CSC actually saw income rise from £298m in 2012.