French Foreign Ministry spokesman Bernard Valero said the Strait of Hormuz was an international strait, "therefore all ships, no matter what flag they fly, have the right of transit passage."
On December 27, Iran's first vice president, Mohammad Reza Rahimi, warned that Iran would block the flow of crude through the strait if foreign sanctions were imposed on Tehran's oil exports over its nuclear program.
And the next day, Iran's top naval commander, Habibollah Sayyari, said closing the strait would be "easier than drinking a glass of water" for Iran if Tehran deemed it necessary
About a third of all seaborne oil is estimated to have been shipped through the strait -- which links the Persian Gulf with the open ocean -- in 2009.
The exchange of comments comes as Iran is midway through 10 days of navy exercises in international waters to the east of the strait.
Tensions over Iran's nuclear program have increased since the UN nuclear watchdog reported last month that Tehran appears to have worked on designing a nuclear bomb.
Iran strongly rejects the charges and says it's developing nuclear energy for peaceful purposes.
compiled from agency reports