In a statement, Solana said he had been surprised to hear that Larijani had postponed his trip to Brussels.
Solana said he spoke with Larijani on the phone and they agreed the meeting will take place on July 6, and that discussions will continue on July 11.
Solana and Larijani are expected to discuss a package of incentives offered by major powers to persuade Iran to halt uranium enrichment.
The EU has urged Iran to reply quickly to the offer, but Iran has previously said it may not give a final answer before August 22.
European Commission spokeswoman Emma Udwin on July 5 reiterated the call for an earlier response.
"We and other members of the EU have expressed disappointment at Iran's slowness in coming forward with a response to the very good package that has been offered by the EU and backed by other members of the international community," Udwin said. "We think that it's important that there is a response and [that it comes] sooner than the Iranians have indicated."
(compiled from agency reports)
RFE/RL Iran Report
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