Class of '92 stars David Beckham, Paul Scholes, Nicky Butt, Ryan Giggs and Phil and Gary Neville arrived at the documentary's premiere at Leicester Square.
The former England captain attended the event with wife Victoria, and the couple's three sons Brooklyn, Romeo and Cruz.
When asked about reports that Beckham could become Sir David in the New Year Honours List, Styles replied: "Why not? He's a national treasure isn't he? It makes sense. I thought he was already."
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The UN has said it is deeply concerned by reports hundreds of Syrian men have disappeared amid a mass exodus from rebel-held areas.
A man suspected of planning a terrorist attack has been arrested in Rotterdam after police found a loaded AK-47 in his apartment.
Another mild day with highs reaching up to 13C degrees in mild southerly winds