An armed Russian fighter jet flew alarmingly close to a U.S. Navy reconnaissance aircraft flying in the Black Sea on Tuesday -- just one day before Russian Foreign Minister Sergey Lavrov visited Washington.
The Russian jet came as close as 20 feet to the American aircraft and remained that close for five minutes, a U.S. defense official told Fox News.
The Russian jet was carrying six air-to-air missiles under its wings, making this episode "highly provocative," one official told Fox News.
It is very rare for a Russian jet to intercept a U.S. aircraft while visibly armed, officials said.
"This was a one off," one official said.
Earlier, officials described the encounter as "safe."
"While this one was considered by the flight crew to be safe and professional, this sort of close encounter certainly has the possibility to become dangerous in a hurry," the defense official said.
A Su-27 Russian jet made the close approach to the P-8A Poseidon while the Navy plane was in international airspace.
The Su-27 was scrambled reportedly after the Poseidon appeared to be approaching Russia's border. The Poseidon soon changed its course.
In a statement issued Friday, the Russian officials called the jet's intercept a "greeting" maneuver.
"After approaching a plane at a safe distance the Russian pilot visually identified the flying object as a U.S. surveillance plane P-8A Poseidon," the Russian military said in the statement.
Unlike Russian intercepts in the past, this Russian jet approached the U.S. Navy recon plane "slowly," according to the defense official. The entire encounter lasted about an hour.
"It goes on almost every day of the week," the official said. A separate official said about 60 such incidents have occurred since 2007, RT reported.
The latest Russian incident in the Black Sea comes a month before the U.S. military kicks off a series of military exercises in the region.
In February, Russian fighter jets buzzed a U.S. Navy destroyer in the Black Sea on the same day the U.S. Army unloaded dozens of tanks and hundreds of soldiers in a nearby Romanian port along the Black Sea.
The same destroyer the Russians buzzed in February -- USS Porter -- was one of the warships which launched cruise missiles into Syria last month.
In September, a Russian jet buzzed a Navy spy plane over the Black Sea, the aircrafts coming within 10 feet of each other during that encounter.
When asked about the timing of Tuesday's incident coming a day before Lavrov's visit to Washington to meet President Trump and Secretary of State Rex Tillerson, the defense official asked, "What were we doing flying that day?"
The latest Russian provocation comes a week after a pair of Russian Bear bombers and fighter jets flew near Alaska on several consecutive nights, prompting the U.S. Air Force to dispatch F-22 stealth fighter jets to intercept the Russian formation.
NBC News was the first to report Tuesday's intercept.
Lucas Tomlinson is the Pentagon and State Department producer for Fox News Channel. You can follow him on Twitter: @LucasFoxNews