A leading US senator has said that President Obama knew of an “unprecedented action” taken by the CIA against the Senate intelligence committee, which has apparently prompted an inspector general’s inquiry at Langley.

The subtle reference in a Tuesday letter from Senator Mark Udall to Obama, seeking to enlist the president’s help in declassifying a 6,300-page inquiry by the committee into torture carried out by CIA interrogators after 9/11, threatens to plunge the White House into a battle between the agency and its Senate overseers.

“As you are aware, the CIA has recently taken unprecedented action against the committee in relation to the internal CIA review and I find these actions to be incredibly troubling for the Committee’s oversight powers and for our democracy,” Udall wrote to Obama on Tuesday.

Independent observers were unaware of a precedent for the CIA spying on the congressional committees established in the 1970s to check abuses by the intelligence agencies.

“In the worst case, it would be a subversion of independent oversight, and a violation of separation of powers,” said Steven Aftergood, an intelligence analyst at the Federation of American Scientists. “It’s potentially very serious.”

Yes, it is.

Prediction: Udall will stand down and claim that his “as you are aware” reference is being misunderstood. Not that it’s truly being misunderstood, of course. The inference is perfectly clear, and inferences from Udall standing down will also be clear.

h/t Instapundit