Germany's Federal Intelligence Service (BND) Deputy Director-General Ole Diehl said that Russia could test NATO's willingness to implement Article 5 of its collective defense treaty.
"Russia will try to test the integrity of Article 5 of the NATO charter," Dale said in a speech at the Delphi Economic Forum, held in Greece from April 9 to 12. "We won't see Russian tanks in Berlin, but they might in Estonia."
He continued: "All European capitals will be asked to decide whether to implement Article 5," which stipulates that an attack on one NATO member is considered an attack on the entire alliance.
Commenting on the situation in Ukraine, Dale said that what is happening there "concerns not only Ukraine, but also the security of Eastern European countries... and the security of the United States as well, although it does not see it that way at the moment."
He expressed his opinion that "this is not a clash in which the Russians seek to invade part of the former Soviet Union. Rather, they want a new security system. They want to have a voice in European countries."
Dale considered Russia one of the main "threats" threatening Germany, along with immigration.
It's worth noting that Russia has repeatedly denied allegations of any aggressive plans or intentions. Russian President Vladimir Putin said in an interview with American journalist Tucker Carlson last year that Russia has no intention of launching an attack on NATO countries.