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. Last Updated: 07/27/2016

Critical Next Steps With Iran

Derailing Iran's drive to build nuclear weapons is too important a goal to let fantasies interfere. The point of the intricate diplomacy now getting under way is not to punish the Iranian people with sanctions or overthrow the Islamic republic but to terminate its nuclear enrichment programs before they reach the point where Iran can produce nuclear weapons.

That is a goal that all five permanent members of the United Nations Security Council share, and one they have a chance to achieve if they take a sufficiently united and sufficiently tough stand. The next few weeks will determine whether unity can be preserved without sacrificing toughness.

The decisive factor will be how Russia plays its potentially pivotal hand. This is President Vladimir Putin's big chance to step up to the responsible international leadership role symbolized by his chairmanship, this year, of the developed world's Group of Eight leading industrial countries.

The best remaining chance for a diplomatic solution would require Iran to halt its recently resumed uranium enrichment activities and agree to a Russian proposal that Washington accepts in principle but Tehran has previously rejected. Under this Russian formula, the crucial details of which still need to be nailed down, those uranium enrichment activities most critical to weapons production would be moved out of Iran and carried out on Russian soil and under close Russian supervision.

But there seems little chance that Iran will agree to this proposal unless it clearly understands that rejecting it will mean universal international ostracism.

Iran moved as far as it has on nuclear weapons development by successfully dividing the countries that could and should be drawing and enforcing clear red lines. That division now needs to come to an end.

It will not be enough for Moscow to stand on the sidelines while Western countries play the bad cop with Tehran. Russia needs to play an active role in convincing Iran that it must step back from the brink and renounce its efforts to develop a fully independent nuclear enrichment cycle. Without such a cycle, Iran cannot proceed further toward building its own nuclear bombs.

The International Atomic Energy Agency's governing board meets early next month to consider sending the Iranian issue to the Security Council. That is where the matter now needs to go, after Tehran has ignored the agency's expressions of concern over its nuclear activities and provoked European negotiators by restarting its uranium enrichment activities. Moscow has indicated it will not block such a referral, but that is not enough.

The United States and Europe are not asking the Security Council to impose economic sanctions now. What they want is a statement or resolution that backs up the IAEA's authority and sends Iran a united message that its current course is dangerous and unacceptable. Iran will find it much harder to ignore that message if Russia, which has been its main nuclear technology partner in the past, actively supports both the referral and whatever kind of statement the Security Council ultimately decides on.

If China joined these actions as well, the chances of achieving a successful diplomatic resolution would be still greater. If Russia and China are the champions of multilateral nuclear diplomacy they have long claimed to be, now is the time to show it.

This comment first appeared as an editorial in The New York Times.