The key partners in the deal signed a memorandum on Thursday at the worldwide economic forum presently taking place in St. Petersburg, Russia.

Earlier, Gazprom CEO Alexey Miller said that the construction of the first stretch of the Turkish Stream would start in late June.

Russian energy giant Gazprom announced Thursday that it was intending to construct two a double pipeline from Russia to Germany through the Baltic Sea with E.ON, Shell and OMV.

Talks between Turkish and Russian officials about a proposed underwater gas pipeline have been postponed until next week. Its annual capacity after the anticipated December 2016 date of operability is estimated at 63 billion cubic meters. The two countries have also argued on several occasions over delivery prices and gas debt, with Moscow initially allowing the construction of the Nord Stream pipeline in order to reduce dependency on Kyiv. The larger part of the Turkish Stream pipeline will run across the Black Sea and coincide with the South Stream route approved earlier.

According to reports in Russia’s Sputnik and Chinese CNPC, Burmistova stated that in regard to ongoing discussions on the currency, “the purchase-sale contract has not yet been signed and for that reason the payment currency has not yet been determined”.

Gazprom says it’s not going to disclose the pricing formula for gas supplied to China via the western route because negotiations are underway, and pricing is a commercial secret, she added.