Gazprom has not yet announced the beginning of the construction of the second pipeline's string.
Meanwhile, Allseas told the newspaper that 100 kilometers (62 miles) of the first string of the pipe had already been laid, providing though no information on the second string.
By the way, Russia's Gazprom energy company is preparing for construction of the Turkish Stream pipeline's second leg in shallow waters, Gazprom Press Secretary Sergey Kupriyanov told Sputnik on Wednesday.
"Preparatory measures in shallow water [are underway]," Kupriyanov said after an official and a contractor were cited in the Russian press as saying that up to 15 miles of the pipe had been laid along the bottom of the Black Sea without an announcement.
In October 2016, Moscow and Ankara signed an intergovernmental agreement envisioning the construction of two underwater legs of the Turkish Stream gas pipeline in the Black Sea. The annual capacity of each leg is estimated to reach 15.75 billion cubic meters of natural gas. Pipe-laying work for the pipeline is expected to end in late 2019.