IT was good news yesterday that the United States is now willing to sit down at the same table as Iran to negotiate on Tehran's nuclear ambitions. This distinct shift in the US's position is conditional on Iran agreeing to halt its programme of uranium enrichment and accompanied by tough talk from Condoleezza Rice: “The President is not going to take any of his options off the table, temporarily or otherwise.” Hopefully, President Mahmoud Ahmadinejad will resist the temptation to respond too abruptly with his own brand of tough talk; he should show better manners than President Bush did when refusing to respond in any way to the letter that Ahmadinejad sent him a couple of weeks ago. By offering to extend the diplomatic process and securing tacit support to do so from the permanent members of the UN Security Council, and of Germany, the United States has regained some of the ground it had lost by its earlier refusal to texchange views with Iran. Even an initial refusal to participate by Tehran would not necessarily be the end of the story. The White House said yesterday that the initiative followed telephone discussions with Presidents Chirac and Putin and Chancellor Merkel. There was no mention of a call to John Prescott at No 10, but let's be charitable and assume that President Bush and Tony Blair reached agreement on the matter during their meeting at the end of last week.