President Obama today honored Queen Elizabeth's 60 years on the throne, sending her the "heartfelt congratulations of the American people" on the historic occasion of her Diamond Jubilee.

Addressing "Your Majesty" in a video message, Obama describes the queen as "both a living witness to the power of our alliance and a chief source of its resilience."

"In war and in peace, in times of plenty and in times of hardship, the United States and the United Kingdom have shared a special relationship. We've stood tall and strong and together we've faced some of the greatest challenges this world has known," he says.

While many U.S. presidents and British prime ministers have come and gone, Obama notes "your majesty's reign has endured."

"As a steadfast ally, loyal friend and tireless leader, your majesty has set an example of resolve that will be long celebrated," he says.

Looking to the future, Obama says it is "gratifying to know that the bonds between our nations remain indispensable."

"May the light of your majesty's crown continue to reign supreme for many years to come," Obama concludes.