A Royal Navy spokesman said: “An issue with a shaft seal has been identified during HMS Queen Elizabeth’s sea trials. This is scheduled for repair while she is alongside at Portsmouth.
“It does not prevent her from sailing again and her sea trials programme will not be affected.”
The aircraft carrier weighs 65,000 tonnes and has a top speed in excess of 25 knots.
A number of shipbuilding yards around Britain were involved in its construction, including Govan and Scotstoun in Glasgow, Appledore in Devon, Cammell Laird in Liverpool, A&P on the Tyne in Newcastle and Portsmouth.
About 10,000 people worked on construction at the yards before the sections were transported to Rosyth, Fife, where the ship was assembled.
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