Donald Trump discovers mysterious letter from Joe Biden in Oval Office desk before he left office

Donald Trump has revealed an insight into a 'very important' letter he discovered written by former US President Joe Biden.

On Monday (January 20), during a ceremony in the Oval Office located in the West Wing of the White House in Washington DC, 47th President of the US Donald Trump discovered a handwritten letter in a desk from Joe Biden.

Finding the letter

A video shared by Forbes Breaking News shows the moment a journalist asked Trump if he'd received a message from Biden, prompting Trump to open the drawers of the desk.

Quickly finding a letter with the number '47' written on it, Trump commented: "It could have been years before we found it. Wow, thank you.

"[...] Peter thank you very much, I may've not seen this for months."

Trump noted he 'left [Biden] one in the desk just like this' after his term as the 45th president from 2017 to 2021.

And when asked what he spoke about in the letter to Biden, Trump said: "The unification of our country."

But what did Biden's letter to Trump say?

The contents

Well, without giving much away at all, Trump revealed: "It said, 'To Number 47'."

He added: "It was a very nice one [...] just basically a little bit of an inspirational-type letter. Enjoy it. Do a good job. Important, very important how important the job is."

While the specific contents of the letter remain somewhat of a mystery, the practice of the words of wisdom being passed on to the next president isn't - with the letter a tradition in the history of presidents in the US.

The history

The tradition of writing a letter to the incoming president was first started in 1989 by 40th President of the US Ronald Reagan.

Reagan served as president of the US from 1981 to 1989 and upon his leaving of the position, he left a letter to vice president and successor George H.W. Bush.

The letter was written on a piece of paper stationary which already had the comment: "Don't let the turkeys get you down."

It continued: "Dear George, You’ll have moments when you want to use this particular stationary. Well, go to it.

"George, I treasure the memories we share and I wish you all the very best. You’ll be in my prayers. God bless you & Barbara. I’ll miss our Thursday lunches. Ron."

Oh, and there was also an illustration of an elephant surrounded by turkeys - as you do.