RUKLA, Lithuania, Oct 8 (Reuters) - NATO must do more for common security to protect itself against the potential acts of Russia and president Vladimir Putin, German Defence Minister Christine Lambrecht said on Saturday.

"The fact is that we, NATO, must do more for our common security because we cannot know how far Putin's delusions of grandeur can go", Lambrecht said while visiting German troops deployed in Lithuania.

"We've heard Russia's threats to Lithuania which was implementing European sanctions on the border with Kaliningrad. This is not nearly the first threats and we must take them seriously and be prepared," she said.