Iran's chief nuclear negotiator will meet European Union foreign policy chief Javier Solana in Geneva on July 19 for talks on Iran's disputed nuclear programme, an Iranian national security official said on Friday.

The visit follows a visit to Iran in June when Solana presented a package of incentives proposed by world powers to coax Iran to halt sensitive nuclear work the West fears is aimed making bombs, a charge Tehran denies. Iran has offered its own package to resolve the standoff.

Tension increased this week after Iran tested missiles in the Gulf and the United States reminded Tehran that it was ready to defend its allies. Fears of conflict helped to push oil prices back over $143 a barrel on Friday.

"Based on Solana's invitation, Saeed Jalili will meet Solana in Geneva on July 19 to discuss the nuclear package," Ahmad Khademolmelleh, spokesman for Iran's Supreme National Security Council, said in a statement sent to Reuters.

EU officials have in the past preferred European countries as the venue for such meetings. Khademolmelleh said Jalili and Solana would discuss the "common points" in the packages proposed by the world powers and by Iran.

Tehran has repeatedly refused to suspend its uranium enrichment activities, as demanded by the six world powers before formal negotiations can begin on the offer, which includes help to develop a civilian nuclear programme.

Iranian President Mahmoud Ahmadinejad has called any such demand "illegitimate".

Western diplomats say the powers - the United States, Britain, France, Germany, Russia and China - have conditionally offered to hold preliminary talks ahead of formal discussions.

Even for preliminary talks, the big powers say Tehran must freeze any expansion of its nuclear programme in return for the U.N. Security Council halting further sanctions measures.

Iran has given no indication it will accept such a freeze.

Enriched uranium can be used as fuel for power plants but also, if refined much more, as material for nuclear bombs.

The United States, its European allies and Israel accuse Iran of trying to build nuclear bombs under cover of a civilian programme. Iran says its programme is only for electricity.