The only thing more predictable than a story every few weeks about Iran’s nuclear progress are the caveats that it’s not time to worry just yet. I guarantee that the very last news article written before the announcement that they’ve got the bomb will end with reassurances that it could be months or even years before the west has to act.

So relax! Nothing to fret about.

In a development that comes as the Obama administration is drawing up its policy on negotiations with Tehran over its nuclear programme, UN officials said Iran had produced more nuclear material than previously thought.

They said Iran had now accumulated more than one tonne of low enriched uranium hexafluoride at a facility in Natanz. If such a quantity were further enriched it could produce more than 20kg of fissile material – enough for a bomb…

However, UN officials emphasise that in order to produce fissile material Iran would have to reconfigure its Natanz plant to produce high enriched uranium rather than low enriched uranium – a highly visible step that would take months – or to shift its stockpile to another clandestine site…

A senior UN official added that countries usually waited until they had an enriched uranium stockpile sufficient for several bombs before proceeding to develop fissile material. But he conceded that Iran now had enough enriched uranium for one bomb.

How long would it take to turn their stockpile into 20kg of weaponized uranium? Depends on how many centrifuges they’re using to enrich it. Could be six months — or it could be much, much sooner. Of course, like the story says, that depends in turn on whether they have any clandestine enrichment sites set up. Could be that they don’t — or it could be that they have 10 to 15 of them. No wonder Ahmadinejad considers the matter of Iranian nukes “closed.” Exit question one: Er, didn’t the NYT already break this story in November? Exit question two: Is The One still planning to move full speed ahead on negotiations with Iran after they have the bomb? Offhand, I can’t recall anyone putting that question to him, but given our North Korea policy, I can only assume the answer’s yes. That’ll make for a lovely incentive for other countries weighing their proliferation options.