Russia's Deputy Prime Minister Dmitry Rogozin admitted the ships' shortcomings Saturday, RIA Novosti reported.
"It's very odd that ships for offloading a landing force, floating in our latitudes won't work in temperatures below 7 degrees (Celsius)," Rogozin said in a meeting of the Academy of Military Science.
Rogozin did not explain why the ships would not work in cool temperatures.
Russia and France signed the $1.6 billion deal for two of the Mistral ships, the first of which will be delivered in 2014, in June 2011.
The deal came under fire Thursday when Military-Industrial Commission Deputy Head Ivan Kharchenko described it as "absurd" and alleged it would harm the Russian shipbuilding industry