4.6. Modifying supply contracts
See section 2.10. for general information on modifying contracts.
Leaving aside varying the quantities according to Article 22 of the Special and General Conditions (see below) before contracting and/or during the execution of the contract, the contracting authority may under no circumstances increase the budget of the initial supply contract or agree to/arrange for the purchase of equipment that was not covered in the initial tender and subsequent contract.
The only exception to this rule is for additional deliveries by the original supplier intended either as a partial replacement of supplies or installations included in the original contract, or as an extension of existing supplies or installations where a change of supplier would oblige the contracting authority to acquire equipment having different technical characteristics which would result in either incompatibility or disproportionate technical difficulties in operation and maintenance. The additional deliveries arrangement is regarded as a negotiated procedure (see point 22.214.171.124. c) and an addendum or a new contract should be signed.
Under Article 22 of the General Conditions, the contracting authority has the power to issue an administrative order on variations. The contractor is bound to comply with the variation order.