Russia is working to free seven of the 13 seafarers kidnapped off a tanker in the Gulf of Guinea last week.

The country's foreign minister, Maria Zakharova, confirmed on Monday that roughly half the seafarers taken off the 11,322-dwt Curacao Trader (built 2007) last Friday were Russian nationals, according to state-run news agency TASS.

"The Russian embassies in Abuja and Cotonou are constantly in contact with relevant Nigerian and Beninese agencies as well as representatives of the shipowner company.