A United Airlines plane has declared an emergency after leaving London, Aviation Source News reports. Aircraft N665UA had to make a U-turn.

The plane had recently took off from Heathrow before it declared an emergency, and performed a u-turn in the air ahead of an urgent landing back at the airport.

United Airlines flight UA147 was headed for Newark in New York City but delared an issue while still over the skies of the UK.

After sending an emergency code, the plane which is believed to have been in service for around 28 years, performed a u-turn in mid air, reports The Mirror.

Online reports show the plane, a Boeing 767, is preparing to land back at Heathrow Airport - a few minutes after those onboard had left to fly to New Jersey.

A spokesperson for United Airlines told Express: "United flight 147 returned to London Heathrow airport to address a potential mechanical issue.

"The flight landed safely and was subsequently cancelled. We are working to rebook customers on the next available flight to Newark."

According to the airline, the plane was a Boeing 767-300 and was holding 70 passengers plus 11 crew members.

A flight map from Flight Radar 24 shows the flight path for the plane which set off from Heathrow and returned back to the airport after traveling across the south of England.

Express has contacted Heathrow Airport for comment.

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