The Senate was about to pass a bi-partisan bill imposing tough sanctions on Iran through "unanimous consent" - that means no floor debate or discussion.

But Rand Paul, Kentucky's 'Tea Party' senator, objected, which immediately prevents the easy passage.

According to a notice from his office, Paul wants insert an amendment, "that would ensure that nothing in the act shall be construed as a declaration of war or an authorization of the use of force against Iran or Syria, and that any such use of force must be authorized by Congress."

Manu Raju from Politico also has the story:

"Our young men and women, our soldiers, deserve thoughtful debate," Paul, the tea party freshman with libertarian leanings, said on the floor. "Before sending our young men and women into combat, we should have a mature and thoughtful debate over the ramifications of war, over the advisability of war and over the objectives of war."

From Josiah Ryan's report in The Hill:

"Many in this body cannot get boots on ground fast enough in a variety of places, from Syria to Libya to Iran," said Paul. "[I] urge that we not begin a new war without a full debate, without a vote, without careful consideration of the ramifications of a third or even a fourth war in this past decade."

Senator Harry Reid objected to Paul's assertion that the sanctions bill could be used to launch a war.