Bush administration officials initially asserted that the North had a clandestine uranium program under way in 2002.

But recently, government officials said they were no longer as confident that the North built on that purchase and had a uranium program.

But intelligence officials have said they do not know where the uranium program is.

Experts say the uranium programme disclosed in November 2010 could give the communist state a second way to make nuclear weapons.

The North denies having a uranium program.

"So if you hit the plutonium plant, they would just speed up on the uranium program."

The North also agreed to provide full details on its long-rumored uranium program.

The uranium program is based on enrichment equipment and know-how purchased from Pakistan's former nuclear chief.

He's not asking for an apology - just an acknowledgement that the Bush administration was right about the North's uranium programme.

Despite that history, the new agreement does not explicitly address the existence of a uranium program.