The Queen sent a private message to Joe Biden ahead of his being sworn in as president.
A private message from the monarch was sent to Mr Biden ahead of the inauguration ceremony on Wednesday, HELLO! understands.
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Joe Biden is likely to meet the Queen at some point after his inauguration in January; Her Majesty has met every US President, except Lyndon B Johnson, since her reign began in 1952.
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But there is one member of the royal family that Joe has already met - Prince Harry - and it seems that the pair have struck up a sweet friendship over the years.
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The President's wife Dr Jill Biden first met Harry during his tour of the US in 2013, during which he attended a reception for British and US wounded warriors in Washington.
At that time, Mr Biden and Dr Biden were Vice President and second lady under President Obama's administration.
They have since been seen together on a handful of occasions.
Prince Harry and the Bidens in 2017
Although Harry and his wife, Meghan Markle, did not explicitly express their personal political views or endorse a party in the lead-up to the 2020 US elections, they did speak about the importance of voting.
Doting mum Meghan said: "Every four years we are told the same thing, that this is the most important election of our lifetime.
"But this one is. When we vote, our values are put into action and our voices are heard. Your voice is a reminder that you matter, because you do and you deserve to be heard."
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