Russia's main Black Sea oil port of Novorossiisk remained closed on Friday, with a gale warning in force, shipping sources said.
They said winds could be as high as 23 metres per second, while swells were up to three metres.
Novorossiisk, which normally handles about 900,000 barrels per day, has been closed since Wednesday evening.
Sources in Moscow said there were no plans to close the Transneft pipeline, though that could change if the port remained closed as storage space is limited.