Aluminum tubes purchased by the nation of Iraq were intercepted in Jordan in 2001. In September 2002 they were publicly cited by the White House as evidence that Iraq was actively pursuing an atomic weapon. Prior to the 2003 invasion of Iraq, many questioned the validity of the claim. After the invasion, the Iraq Survey Group determined that the best explanation for the tubes' use was to produce conventional 81-mm rockets; no evidence was found of a program to design or develop an 81-mm aluminum rotor uranium centrifuge.