What is the logic behind Iran's strategy?

The Iranian leadership should ask itself what it gains by refusing to negotiate over its nuclear programme. So far the answer appears to be economic pain and universal condemnation.

Western powers are once again readying a deal to end the impasse over Iran's nuclear programme. And once again, Iranian officials are baulking. Ali Asghar Soltanieh, the country's representative to the International Atomic Energy Agency, told Reuters this week that he sees "no logic" in the latest fuel-swap proposal.

This rhetoric should be predictable by now. After years of false promises and an intentionally ambiguous nuclear policy, isn't it time for Tehran to come to terms with its own irrationality?

Last October, discussion in Vienna of a far less stringent fuel-swap deal started well and then fizzled fast. A similar course appears to be playing out now. While Iran has indicated it is open to fresh talks with the EU later this month, no date has been set and the meeting's agenda remains murky.

Economic sanctions have been US president Barack Obama's preferred course of action to counter Iran's back-tracking. The effort appears to have teeth but patience for this approach may be waning, as the Republican Party now has more power in Washington, and their more hawkish instincts are likely to make discussions of military options more frequent.

Iran does have legitimate grievances. As a signatory to the Nuclear Non-Proliferation Treaty, Tehran is entitled to the peaceful pursuit of civilian nuclear power. And members of the UN Security Council have said as much. Iran could have nuclear power without enriching its own uranium to weapons-grade quality, which is the first step to building a bomb. And that's what the proposals offered by the EU and P5+1 aim to guard against.

No one beyond the ruling mullahs knows the true state of Iran's political affairs, though there are signs of fissures that sanctions may exploit. The Iranian president Mahmoud Ahmadinejad is fending off criticism from the Revolutionary Guard - long a staunch ally - while the country's supreme leader Ayatollah Ali Khamenei continues to struggle for approval from the religious elite.

Calls to cut government subsidies for food and fuel could deepen public enmity. Then again, they could also strengthen the hard-line narrative that Iran's problems are the work of the regime's liberal and Zionist "enemies".

Tough talk from both sides is inevitable. Confrontation is not. Western nations should redouble their sanctions strategies, and China and Russia, frequent critics of the economic approach, should drop their objections and get on board. Hawks in the West should not be so quick to brandish their sabres.

Most important, though, the Iranian leadership should ask itself what it gains by refusing to negotiate. So far the answer appears to be economic pain and universal condemnation. There is, to use Mr Soltanieh's words, "no logic" in that.