NATO's secretary-general Anders Fogh Rasmussen condemned the suicide attack Saturday at Russia's Volgograd railway station that left 14 people dead and vowed to continue working with Russia to combat terrorism.

"I strongly condemn the terrorist attack," Rasmussen said in a statement. "There can be no justification for such barbarous attacks."

"NATO and Russia stand together in the fight against terrorism, including by working together on technology to prevent attacks on public transport systems," he added.

"We will continue to cooperate to improve the safety of our citizens, and the security of our countries," Rasmussen concluded.

The attack was the work of a female suicide bomber who blew herself up at the main train station in the southern city of Volgograd, raising concerns about security just six weeks before the Sochi Winter Olympics.