The Queen has just entered a social media war between the United States and Great Britain.
The British monarchy has posted a video on YouTube, responding to President Barack Obama and first lady Michelle Obama's video challenging Prince Harry to the Invictus Games.
The Invictus Games is an international event where wounded, injured or sick armed services members and veterans compete in sports.
"Hey, Prince Harry. Remember when you told us to bring it at the Invictus Games?" First Lady Michelle asks in the video.
Obama then says: "Careful what you wish for."
Behind them as the video finishes, one the of the US military personnel imitates dropping a mic, and says, "Boom!"
Prince Harry's responding video shows him sitting with 90-year-old Queen Elizabeth, looking at a book about the Invictus Games.
He receives a message on his phone from F.L.O.T.U.S. – the First Lady of the United States.
They watch the video and Her Majesty responds with a withering: "Oh really, please."
The prince turns to the camera, eyebrows raised, and imitates: "Boom!"
Prince Harry and the Obamas have been supporters of the event for personnel and veterans.
The event aims to highlight how sport helps the recovery of servicemen and women.
This year’s competition is taking place in Orlando, Florida on May 8.
See the video