Harry and Meghan's appearance with NATO chiefs in Germany today has stolen a march on Prince William in a PR battle between the two brothers and their wives, an expert told MailOnline today.

The Prince of Wales will travel to New York next week, as part of move to step up his role as a global statesman, to meet United Nations leaders and attend a summit for his £50million Earthshot Prize, which is now in its third year.

William is increasingly popular in the US and his trip has generated much interest across the Atlantic, with all major TV networks bidding for interviews.

But the Duke and Duchess of Sussex met NATO joint force commander General Luigi Miglietta today on the sidelines of Harry's Invictus Games – amid claims by athletes at the event that they felt 'caught up in the royal crossfire' between him and his family.

The couple held hands and smiled beside NATO chiefs and their families, including a large Italian and Dutch armed forces contingent, during the royal-style engagement in Dusseldorf.