NHS chief information officers are being advised to seek central clearance before buying any Microsoft products while a national procurement contract is finalised with the supplier. Until a deal is agreed, all procurement of 'non business critical' products, including upgrades to existing packages, will have to be give the green light from the Cabinet Office. Stephen Kelly, who is leading negotiations for the Government, said in a recent fax to IT chiefs: "It is my intention to develop a commercial arrangement with Microsoft which will provide better commercial terms, reduced cost, and add greater flexibility." He added: "The focus of the Government in its engagement with strategic suppliers is to act with one voice to secure the most-favourable terms, therefore I ask for your continued support and that you refrain from non business critical spend with Microsoft until a new commercial arrangement is secured." The move follows the Department of Health's decision last summer to pull the plug on its 12-year £500m agreement with the solutions giant. A spokesman for the Cabinet Office said: "We are not asking chief information officers to stop buying anything. We are requesting that departments route all potential purchases through the centre so we can assess each on its individual merits."