China said it will be 'difficult' for its representative in Vienna to tour Iran's nuclear facilities, the Foreign Ministry said on Thursday, Reuters reported.
Hong Lei made the comments at a regular news briefing.
The European Union had turned down an offer from Iran to tour its nuclear facilities, EU foreign affairs chief Catherine Ashton said on Friday, but remained optimistic about talks with Teheran later this month, Straits Times reported.
Britain, France and Germany, among the six world powers involved in sporadic talks with Iran over its disputed uranium enrichment programme, were not invited, and neither was the United States. Iran did invite Russia and China.
The West suspects Iran's nuclear programme is directed at developing bombs. Teheran says it is for peaceful energy only.
Western diplomats have described Iran's invitation as an attempt to split the six powers - the United States, Britain, France, Germany, Russia and China - to weaken punitive sanctions against Teheran over its secretive nuclear activity. Russia and China have tended to take a softer line on Iran.