The sale of the Mistral-class tank carrier would mark the biggest arms sale ever by a NATO country to Russia.

French President Nicolas Sarkozy told a news conference that the two countries have started “exclusive” talks toward the possible sale - which has sparked some concern among some NATO allies and Georgia.

He spoke Monday at the start of a state visit by Russian counterpart Dmitry Medvedev.

The Russian leader said the sale would amount to “a symbol of trust between our countries” - and would give Russia the chance “to receive the material we lack.”