An American Airlines Boeing 777-300, performing flight from Dallas Ft. Worth (USA) to London Heathrow (UK), reported lavatory congregation.

• Aircraft was enroute at FL330 about 20nm west of Sydney (Canada) when the crew decided to divert to New York JFK (USA) after one of the toilets got clogged causing three others directly connected to become unavailable, too.
• Flight attendants observed “passengers congregating” in front of the remaining 8 toilets and suggested the continuation of the flight was not safe.
• The aircraft landed safely in New York about 1:50 hours later.