Talks between Russia and France to jointly build two Mistral-class helicopter carriers have broken down, UPI cited officials as saying. The talks ended over Russia's demand that France provide details and production rights for sensitive electronic devices on the ships, something France said it would not agree to, RIA Novosti reported Friday. "The Russian side wants to get all advanced technologies together with the ship and the future of the contract totally depends on whether France would agree to part with these systems," a source told RIA Novosti. Mistral-class ships are equipped with a specialized naval tactical data system, which France apparently wants to keep out of Russian hands. Russia replaced its team of negotiators Thursday, hoping to save the deal, RIA Novosti said. The two countries signed an agreement in January to jointly build two Mistral-class carriers at the STX shipyard in Saint-Nazaire, France. An additional two carriers might be built later at the Admiralty Shipyards in St. Petersburg, Russia. The ships can carry 16 helicopters, 70 armored vehicles, four landing vessels and 450 personnel.