The good news is that Iran and North Korea, in talks about their nuclear programmes, are behaving in a way that you may call rational. The bad news is that the price each is asking for giving up that nuclear investment has not yet approached the realm of reality. In Beijing envoys to the six-party talks on North Korea’s nuclear programme found enough common ground to go into a fifth day of talks about disarmamament.

North Korea had asked for up to two million tonnes of heavy fuel oil, plus two million kilowatts of electricity. The US was right to have refused: it would have removed any further levers over Pyongyang. That deal would have allowed North Korea to renege on any promises it made to mothball or scrap its nuclear installations. The early-hours talk of progress, albeit hedged by many “possibles” and “potentials”, overcame a mood of despondency that had initially hovered over the talks. The possession of nuclear weapons is the only card that Kim Jong Il holds, and it is no surprise that every time he extracts an offer for surrendering it, he wonders if he can get a better one.

The outline deal on which US negotiators have been working tries to break this impasse by marking out tiny steps, measured in months not years. The US would begin by offering little but getting little in return — essentially the scrapping of future activities, but not existing weapons. Despite the sudden, extravagant demand from Pyongyang, which threatened to destroy this scheme, it has shown more willingness to negotiate than it did a year ago.

The same is true of Iran, which appears wrong-footed by the agreement in the United Nations Security Council on sanctions, and the European Union’s steps to replicate them. Yesterday, EU foreign ministers agreed a formula for doing more than “cutting and pasting” the UN resolution. The EU measures stop short of the financial sanctions that the US is pressing it to employ. The EU’s reluctance to take that step will continue to cause transatlantic tension.

At the same time, the many-sided crackdown appears to have given Iranian negotiators pause for thought. So, perhaps, has the US’s weekend assertion that Iran has supplied sophisticated roadside bombs that have killed more than 170 US soldiers — a charge that Iran denies. But if the photographs of bits of bombs are not meant as justification for military action against Iran — an intention the US denies — then it has little point. Iran’s ability to add to the violence in Iraq has not been in doubt; it is dwarfed in significance by its political influence over Iraqi leaders.

The most useful purpose of the US accusations is to add to the pressure on Iran from many sides. Its careful reaction in the past week shows that it is listening.

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