Saudi-led consortium Arkad has filed a complaint against Bulgartransgaz's decision to disqualify it as winner in a multimillion-euro tender for the construction of a pipeline for transit of natural gas to Europe, the Bulgarian competition authority said.The consortium comprising Saudi Arabia's Arkad Engineering and Construction Company and Italy-registered Arkad ABB has filed its complaint against the May 28 decision of the state-owned natural gas transmission network operator to choose the second-ranked candidate as a contractor in the project, the Commission for Protection of Competition said in a notice last week.Bulgartransgaz announced Arkad as winner of the tender but subsequently removed the group from the competition because it failed to meet the deadlines for signing the contract and for submitting the necessary documents - May 2 and May 16, respectively. At the same time, Bulgartransgaz awarded the contract to the second-ranked participant in the tender - a consortium comprising Italy's Consorzio Varna 1 and the Bulgarian branch of Luxembourg-registered Completions Development. The consortium has proposed to build the 484 km-long pipeline between Bulgaria's borders with Turkey and Serbia for 2.41 billion euro ($2.72 billion) within 250 days, or for 1.10 billion euro should the deadline be extended to 615 days.