Queen Elizabeth privately congratulated Joe Biden, Buckingham Palace confirms

Queen Elizabeth sent felicitations to Joe Biden in a private message , ahead of his inauguration as the 46th president of the US, confirmed Buckingham Palace.

Before the star-studded swearing in of Biden and Harris - America's first woman vice president - kick-started, the British monarch reached out to the incoming president, as confirmed by a Buckingham Palace insider.

According to The Sunday Times royal correspondent Roya Nikkhah, the Queen penned a private letter, to show her support ahead of the historic inauguration, as confirmed by Harper's Bazaar.

Meanwhile, British prime minister Boris Johnson also congratulated Biden, via Twitter message, upon his swearing in.

"Congratulations to @JoeBiden on being sworn in as President of the United States and to @KamalaHarris on her historic inauguration," Johnson's public statement read. "America's leadership is vital on the issues that matter to us all, from climate change to COVID, and I look forward to working with President Biden."