One of the most experienced and respected security analysts in the United States has produced a comprehensive study of all the material released so far on Iran's nuclear programme.

In Rethinking Our Approach to Iran's Search for the Bomb, Anthony Cordesman concludes that Iran is irrefutably developing an atomic weapon.

He recommends that the West must, if Iran is to be stopped, go beyond its current sole focus on uranium enrichment and hold Iran to account on all aspects of its nuclear programme.

Mr Cordesman, an expert on security and intelligence at the Centre for Strategic and International Studies in Washington DC, has decades of experience advising US administrations on defence. He was previously considered to have been a sceptic towards the idea that Iran's programme could only have military intent.

The report includes an in-depth look at hundreds of pages of the International Atomic Energy Agency's (IAEA) most recent reports on Iran's nuclear programme, which few analysts have delved into in their entirety.

It comes amid renewed talks this week between Iranian diplomats and the IAEA in Vienna. A fresh round of negotiations between Iran and the five permanent members of the Security Council, along with Germany, are due to take place next week in Baghdad.

Any notion that Iran is carrying out research for non-military purposes is dismissed by Mr Cordesman. Collating the intelligence supplied to the IAEA, he concludes that Iran has been working on a wide range of weapons projects for over a decade. Many have been specifically aimed at the acquisition of a nuclear capability.

He also details how, despite sanctions and international supervision, Iran has imported specialised instruments and equipment, as well as the assistance of foreign nuclear weapons developers.

Iran has also carried out advanced tests on nuclear weapons components and prepared for a test detonation.

The report concludes: "Iran has pursued every major area of nuclear weapons development, has carried out programmes that have already given it every component of a weapon except fissile material, and there is strong evidence that it has carried out programmes to integrate a nuclear warhead on to its missiles."

Mr Cordesman recommends that the West not only focuses on the issue of uranium enrichment, currently at the top of the agenda for the Baghdad talks, but also on all aspects of Iran's nuclear development.

The study has emerged alongside a number of other reports which also indicate that Western powers should not be concentrating solely on the issue of uranium enrichment.

Last week, the National Council of Resistance of Iran (a coalition of exiled opponents of the regime) produced a detailed hierarchy of the nuclear programme's command structure and the names of over 60 scientists and officials working on it.

In addition, the Associated Press this week published detailed drawings of an explosives containment chamber that had allegedly been built on the Parchin base and used to carry out small-scale nuclear tests.

The drawing is based on information supplied to the IAEA by Western intelligence agencies.