The U.S. State Department said on Thursday that North Korea poses a significant cyber threat to the United States and other countries, particularly to financial institutions.

Department spokesperson Ned Price made the remarks during a press briefing when asked to comment on an alleged North Korean cyber attack on South Korea's state-run nuclear research institute. 

Price said that North Korea's malicious cyber activities threaten the United States, its allies and partners, and countries around the world, adding the North "poses a significant cyber threat to financial institutions."

The spokesperson then stressed that it's vital for the international community, for network defenders and the public to stay vigilant and to work together to mitigate the cyber threat posed by North Korea.

South Korea's National Intelligence Service said on Thursday that its state-run Atomic Energy Research Institute may have been exposed to North Korean cyber attacks for 12 days, although there had been no major data leaks as a result of such attacks.