The agreement would allow greater access to EU markets for Iranian products and would mean a significant stepping up of diplomatic ties.

Kamal Kharrazi met the EU's high representative Javier Solana, external relations Commissioner Chris Patten and Commission President Romano Prodi today in a bid to convince the EU that the country had done enough to restart talks.

The EU has pushed a policy of constructive engagement with Iran in contrast to Washington's ostracism of the Islamic Republic.

However after Iran's elections which saw thousands of democratic candidates barred from running, patience is beginning to wear thin on the EU side.

"We have invested a lot of effort and energy into this process over the last five years and frankly we are a little disappointed with the results", Emma Udwin a spokesperson for Commissioner Patten told the EUobserver.

Crunch time

Iran is to make a declaration of its nuclear programmes to the International Atomic Energy Agency later this month.

In June, the IAEA's board of governors will respond deciding if the declaration has been complete and accurately reflects the situation on the ground. Past declarations from the Iranian side have been judged by the IAEA to have been incomplete.

A similar report this time around would put immense pressure on the EU to toughen its line.

The board has been the scene of some tension in the past with the US advocating taking the matter to the UN Security Council in a bid to ramp up the pressure on Tehran.

The EU has so far resisted such calls but may not be able to this time.

EU foreign ministers will discuss the matter of trade talks this summer after the IAEA board has given its verdict.