Any attack on infrastructure critical to the NATO military alliance would trigger a "united and determined response", the NATO Secretary-General Jens Stoltenberg said on Tuesday.
Stoltenberg told a news conference that NATO allies were increasing security around key installations after attacks on gas pipelines running under the Baltic Sea. It is still unclear who was behind the blowing up of the pipelines.
Commenting on veiled threats of nuclear weapons use by Russian President Vladimir Putin, Stoltenberg said that NATO was closely monitoring Russia's nuclear forces and had not seen any changes in their posture.
(Reporting by Jan Strupczewski; Editing by John Chalmers)
