Moscow (AFP) - A NATO military plane on Wednesday approached the plane of Russian Defence Minister Sergei Shoigu above the Baltic Sea, Russian news agencies reported, the third such encounter in three days.
A NATO fighter jet tried to approach Shoigu's plane but a Russian escort plane intervened to defend it, Interfax news agency reported, citing journalists accompanying the minister.
The escort plane, a Sukhoi SU-27, demonstrated it was armed by rocking its wings, after which the NATO plane flew off, Interfax reported.
Russian state television aired defence ministry footage of the incident, reporting that it took place over neutral waters.
Shoigu was flying to Kaliningrad, a highly militarised Russian exclave on the Baltic Sea, to take part in a meeting with defence officials there.
At the meeting, he warned that "the situation near Russia's western borders is tending to get worse," TASS news agency reported.
"This is tied with the upsurge of military activity of the NATO countries in Europe," Shoigu added.
The meeting came after NATO held military exercises at the weekend in Poland on the Lithuanian border close to Kaliningrad.
On Monday a Russian jet fighter identified two "American spy planes" over the Baltic, one of which made a "provocative" manoeuvre, the Russian defence ministry said in a statement.
NATO is deploying four international battalions in Poland and each of the former Soviet Baltic states -- Estonia, Latvia and Lithuania.
Moscow sees the NATO build-up in the region as demonstrating a desire to contain Russia.
On Wednesday, Sweden summoned Russia's ambassador after a Russian Sukhoi fighter jet flew unusually close to a Swedish reconnaissance plane above the Baltic Sea.
"The Russian behaviour is unacceptable" and had increased the risk of a serious incident, Swedish Defence Minister Peter Hultqvist told the TT news agency.
That incident, in international airspace, happened on Monday, a Swedish army statement said.
On the same day, a Russian fighter conducted an "unsafe" intercept of a US reconnaissance plane over the Baltic Sea, the US military reported Tuesday.
Russian fighter jets routinely approach and identify aircraft in the skies over the Baltic and the Russian enclave of Kaliningrad, but most of these actions stay within safe limits.
Both Washington and Stockholm said these latest incidents went beyond those limits.
The protests come at a time of heightened tension between Russia and the United States over Syria, where they are backing different sides in the conflict.