"Outside of G-Cloud, far too often we still don't see a level playing field. CCS can be lumped into the oligopoly of big SIs [system integrators]...it is bereft of any intent to spend 25 percent with SMEs," Chant told the Think Cloud for Government conference in London yesterday.
ComputerworldUK understands tensions between the Government Digital Service (GDS) and CCS have been rising recently.
In a recent speech, government digital director Mike Bracken said Whitehall needs to "let go of our misplaced belief in big IT procurement".
Both he and government CTO Liam Maxwell have warned procurement processes too often act as a barrier to reforms to digitise services and use more SMEs.
Singleton welcomed criticisms of the framework and argued it has not worked as expected. He said: "The amount going through digital services is about half of what it should be."
But Hurrell defended DSf. She said £26 million total contract value let so far, versus an expected £40 million by August 2014, still represented a success. Hurrell said the spending limit for frameworks has to be set higher than expected to stay within EU regulations.
Responding to criticisms of DSf from SMEs listed on the framework, Hurrell claimed CCS has taken "significant steps" to improve it during the latest procurement round (DSf2) and said it was "planning a revolutionary change for DSf3".
She added: "Sometimes people get hung up on one small part of a procurement and risk throwing the baby out with the bathwater.
"You might think it's a nightmare dealing with government as an SME but you should see the red tape we've hacked away already."
A number of firms have aired their complaints about DSf in recent days. Speaking to ComputerworldUK, Harry Metcalfe, founder of digital services agency dxw, said it was "not fit for purpose" as its 'body-shopping' approach shuts out SMEs.
SME Crown Representative Stephen Allott echoed the suppliers' concerns. When CCS was launched "I looked eagerly at the website for any mention of SMEs and didn't find one", he said.
In his speech, Chant claimed CCS acts as an 'old world influence' on government IT by setting up pan-government frameworks that shut out SMEs and hold back innovation.
"You remain in the way, step aside," he said.
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