The Director General of the International Atomic Energy Agency yesterday warned that he cannot confirm that all of Iran’s nuclear activities are for civilian purposes. IAEA chief Yukiya Amano told the IAEA Board of Governors, which is meeting in Geneva Switzerland, that “we cannot confirm that all nuclear material in Iran is in peaceful activities because Iran has not provided the agency with the necessary co-operation.” His statement is a slightly softer indictment of Iran’s nuclear defiance than a confidential IAEA report leaked last week that indicated that the U.N. agency had “concerns about the possible existence in Iran of past or current undisclosed activities related to the development of a nuclear payload for a missile.”

Amano’s statement will add momentum to calls for stronger sanctions against Iran at the U.N. Security Council, where the United States, Britain, France and Germany are pressing Russia and China to sign off on another sanctions resolution against Iran. Although Moscow has opposed calls for new sanctions in the past, Russian President Dmitry Medvedev yesterday indicated that Russia may be willing to consider a new round of sanctions.

But persuading Moscow and Beijing to accede to effective sanctions will require strong American leadership. Unfortunately, the White House has fallen short on the sanctions issue, losing an entire year before pushing for another resolution. Moreover, the State Department has sought to indefinitely postpone gasoline sanctions passed by bipartisan landslide votes in both the House and Senate over the Obama Administration’s objections. This sends exactly the wrong signal about getting serious about penalizing Iran for its nuclear defiance.

The long-overdue push for a fourth round of U.N. Security Council sanctions has been aided by Iran’s rejection of a nuclear deal brokered by the IAEA to move most of Iran’s stockpile of low enriched uranium out of the country in return for fuel for a nuclear research reactor in Tehran.

The push for sanctions also has been aided by the replacement of the IAEA’s longtime Director General Mohamed Elbaradei by Amano in December. Amano has been much more forthright in detailing Iran’s continued failure to cooperate on nuclear issues, in contrast to ElBaradei who often seemed more interested in criticizing the West than carrying out his duties regarding Iran’s suspected nuclear weapons activities. After leaving the U.N. agency that he politicized to carry out his own agenda, Elbaradei now has returned to Egypt where he hopes to exploit his anti-western notoriety to launch a political career. This is a worrisome development for Egypt, but a net gain for the IAEA.

For more on Iran, see: Iran Briefing Room