NBC News has previously reported that Robert Joseph, the National Security Council’s senior director for proliferation strategy, and the CIA’s weapons proliferation director, Alan Foley, argued about whether the reference should have been in the speech.
Sources have told the network that, after Foley objected to the first draft of the passage, Joseph came up with the suggestion of attributing it to the British, asking Foley whether that would make it technically correct.
Because British intelligence officials had made the information public, Foley acknowledged that the passage was factually accurate, even though the CIA did not think the assertion was true, according to the sources.

Same MSNBC article

Technically correct, substantively false...weasel wording inserted into a State of the Union address, deliberately calculated to deceive. Tell me again that the White House didn't knowingly distort the intelligence to back up their sales pitch for war.