The requests for review of the pick by the state-run motorway operator DARS of Cengiz Insaat Sanayi Ve Ticaret have been filed by the Nova Gorica-based builder Kolektor CPG and the Bosnian construction company Euro-Asfalt.

The news comes as the deadline for complaints against the selection of the Turkish company for the project on the 8-km tunnel linking Slovenia's A2 and Austria's A11 motorways expires today.

The Turkish bid at EUR 89.3m, excluding VAT, was by far the cheapest of the nine bids submitted, but the selection is not yet final.

The entire project involves the construction of a new, 3,546-metre motorway tube and a 620-metre motorway section connecting the tube to the existing motorway.

The investment is estimated at EUR 151.6m, VAT excluded, of which construction is budgeted at EUR 121.5m. The construction is estimated to take five years.

Kolektor CGP, which submitted the request for review on 17 August, had submitted a bid in a consortium with the Slovenian engineering company Riko and the Turkish builder Yapi Merkezi, valued at EUR 109.4m.

The revision request by Euro-Asfalt arrived at DARS today. Alongside Cestno Podjetje Ptuj, the company bid to complete the project for EUR 106.3m.

Commenting on Kolektor's request this morning, DARS told the STA that the request would first be examined in-house. If the complainant insisted on the review after receiving an answer, it would forward the request to the National Review Commission next month.

"The request for review could delay the start of construction by two to three months at the most. What is important that the tender does not get annulled," DARS said.

DARS chairman Tomaž Vidic has told the public broadcaster TV Slovenija that the delay of the five-year project could be huge in such a case.

If the Slovenian tender gets annulled, the Austrian side would have to postpone the start of the construction of its part of the tunnel tube, which would cause additional costs for the Austrian motorway operator.

ASFINAG and the selected contractor for the Austrian part, Swietelsky, are planning to start the work already in mid-September. Swietelsky was also the bidder with the lowest offered price in the Austrian tender.

Following the pick by DARS, some Slovenian media accused Cengiz Insaat Sanayi Ve Ticaret of allegedly setting a dumping price, of being a regime company of Turkish President Recep Tayyip Erdogan and of exploiting workers.

Vidic explained that DARS had not examined the bidders' treatment of workers as it had been able to examine only what was permitted by law and defined in the tender documentation.

The selected bidder denied the media reports, saying that their construction sites were subjected to the highest safety standards, strongly rejecting the speculations that hundreds of workers had died at their construction sites.

Cengiz Insaat Sanayi Ve Ticaret said that the work on the Karavanke tunnel would be conducted in line with the Slovenian and EU standards, and that all workers would be treated in line with the relevant laws and rights.

The company has build and is building in Turkey and abroad "a total of 446 kilometres of motorway and railway tunnels within the agreed deadlines and required quality".