Obama will deliver his speech from the steps of the Lincoln Memorial — the same place where King spoke 50 years ago. The Let Freedom Ring ceremony will be held Aug. 28.

"It’s obviously a historic, seminal event in the country. It’s part of my generation’s formative memory and it’s a good time for us to do some reflection," he said in a New York Times interview last month about the anniversary. 

The original rally in 1963 was billed as the March on Washington for Jobs and Freedom. 

Obama has delivered a series of speeches aimed at the economy over the last few weeks, addressing the mortgage crisis in his latest speech in Arizona on Tuesday. 

The president also made a rare appearance in the White House press briefing room last month to speak personally about the black experience in America after the verdict in the shooting death of Trayvon Martin. It was one of the first and most detailed statements he has given on the topic since his famous speech during the 2008 election. 

"Obviously, after the Trayvon Martin case, a lot of people have been thinking about race, but I always remind people — and, in fact, I have a copy of the original program in my office, framed — that that was a march for jobs and justice; that there was a massive economic component to that," he said in the interview.