The Olympics Airlines plane had been traveling from Athens to New York's JFK airport when it was diverted to the Essex airport, escorted by British Tornado jets.
The emergency landing came after an Athens-based Greek newspaper, Ethnos, received a telephone call saying that there was a bomb on board the flight.
The Greek authorities are then believed to have notified the pilot, who asked for a military escort.
A Ministry of Defence spokesman confirmed that the planes were scrambled after the RAF "received a request for assistance by the civilian authorities".
"The RAF responded and escorted the aircraft until it had landed safety. The aircraft then returned to base."
A Stansted airport spokeswoman said: "I can confirm Olympic Airlines flight 411 from Athens to JFK was diverted into Stansted on a full emergency.
"This afternoon it landed safely just after 3.30pm. There were 301 passengers [and crew] on board, all of whom have been evacuated safely."
Essex police have boarded the jet and are presently searching for any suspect devices. If nothing is found in the sweep the plane is expected to continue to New York.
A spokeswoman for Essex police said that the incident was being treated "as an emergency landing". Essex fire services also said they were attending the scene.
.png?w=600)
