First Officer reported approximately 45 minutes after takeoff at cruise altitude; observing the right engine fire warning light begin to flicker on. The flight crew performed an air turn back; dumped fuel and made a precautionary landing at departure airport.

Narrative

Approximately 45 minutes after takeoff at cruise altitude; we observed the right engine fire warning light begin to flicker on. It increased in frequency and duration. The Captain initiated a Sat phone call to Dispatch and Maintenance Control. While this call was occurring the light became more frequent and persistent. As we were only about one hour from ZZZ with many souls on board; we made the prudent decision out of an abundance of caution to return to ZZZ versus continuing on further away from a safe landing spot. A priority report was made to ZZZ1 (ZZZ Center) and clearance was received to return to ZZZ. We began to dump fuel as to not exceed our maximum landing weight. Checklist were run and we briefed the Flight Attendants; announcements were made to the passengers and contingencies discussed. Arrival; approach and landing were normal. We were met by the fire department upon clearing the Runway; the right engine was shut down and inspected by the fire personnel for any noticeable damage; there was none. As we had been directed to an awkward position on the Taxiway for the fire crews to inspect the engine; we were unable to taxi the aircraft to the Gate and we required a tug to tow us to the Gate. Passengers were disembarked and Maintenance personnel entered the flight deck to ascertain the nature of the problem.