Prince William jokingly told employees at BAE Systems in Barrow-in-Furness, Cumbria that they can "get back to work" after watching him unveil a plaque at the factory.
The occasion was to mark the opening of a new suite of offices where the next generation of Britain's nuclear submarines will be designed.
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Some dense fog is likely in the southeast, whilst brighter breaks are possible across eastern Scotland, northern England and north Wales.
When asked if he was joking or not, Mr Biden paused briefly before saying: "I’m not committing not to run. I’m not committed to anything."
"Calls and emails are coming in all the time" from players who say they had been forced to sign non-disclosure agreements, it was claimed.