Canada, India, Singapore and Egypt are "seriously" interested in buying France's two Mistral warships, a senior official has said, after Paris scrapped a deal to sell the vessels to Russia over the Ukraine crisis.

Louis Gautier, an official who advises the prime minister on defence and security matters, also told lawmakers this week that the cost of abandoning the agreement with Russia would be at least 1.1 billion euros ($1.2 billion) if the government did not sell the ships to other countries, according to a summary of his comments obtained by AFP Friday.