Washington, Sep 11 (DPA) The US Thursday criticised Iran's proposal for resolving the long-standing nuclear dispute, saying it failed to address the key issues that have put Tehran at odds with much of the international community.

State Department spokesman P.J. Crowley said Iran's offer, submitted Wednesday, was 'not really responsive to our greatest concern, which is obviously Iran's nuclear programme'.

'Iran reiterated its view that, as far as it is concerned, its nuclear file is closed,' Crowley said. 'That is certainly not the case. There are many outstanding issues.'

Exact details of the proposal have not been released. Crowley said the five members of the UN Security Council - the US, China, Russia, France and Britain - plus Germany were considering a formal response. Officials from the six countries held a conference call Wednesday and would hold another one Friday.

Iran has long insisted that its nuclear programme is solely for peaceful purposes.