Ewen MacAskill, diplomatic editor
The Iranian government carried out a missile test yesterday, 24 hours before a make-or-break meeting with Britain, France and Germany on its suspected nuclear weapons programme.
The test may have been intended as a warning to the US, Israel and the Europeans on the eve of the meeting in Vienna with the European troika.
Tehran has threatened to retaliate if either the US or Israel launches a pre-emptive strike on its nuclear facilities.
Yesterday it said it had tested the Shahab-3 ballistic missile, which is estimated to be capable of reaching Israel.
The defence minister, Ali Shamkhani, told Reuters after the weekly cabinet meeting: "Iran test-fired a more accurate version of the Shahab-3 in the presence of observers."
The Shahab (meteor) has a range of about 807-932 miles but, until now, it has been regarded as wildly inaccurate, unable to hit military targets but capable of hitting civilian populations.
A Foreign Office source described today's meeting as a "last chance" for Tehran. The US, Israel and Europe are convinced that it is intent on securing a nuclear weapon. Iran denies this, claiming it is only pursuing a civilian nuclear programme.
The European trio will offer help with the civilian programme in return for Iran suspending a nuclear enrichment programme alleged to give it the ability to make nuclear weapons by 2006 or 2007. The Europeans expect a formal response from Iran in about a week.
Its failure to do so will almost certainly cause an international crisis. The board of the International Atomic Energy Agency, the UN nuclear watchdog, is likely to refer the issue to the UN security council when it meets in Vienna on November 25. The council could then impose sanctions.
Tehran combined its missile test with a softer approach by President Ayatollah Mohammad Khatami, who said: "We are ready to assure the world that we are not pursuing nuclear weapons and I believe the only way is through talks and reaching an understanding. I don't know what the [EU trio's"> proposal is, but we are ready for talks.
"But at the same time we are expecting that they do not force us to abandon peaceful nuclear technology under the full supervision of the International Atomic Energy Agency."
The Europeans are pessimistic about the chance of Iran agreeing to the package. The meeting is, in part, intended to allow the three to say that they have explored all possible options.
The news agency Agence France-Presse reported yester day that it had obtained a copy of the three countries' package of incentives.
The document said: "We would support the acquisition by Iran of a light water research reactor." It added that there was only "a short period of time [left"> to secure a comprehensive and acceptable understanding from Iran".
The three would also "be ready to resume negotiations on an EU/Iran trade and co-operation agreement" and back Russia's building of a nuclear reactor for Iran in Bushehr. The Europeans secured a deal with Iran in October last year but say that Tehran has reneged on it.