Iran has been at the center of an international dispute this year over its nuclear ambitions. Some countries suspect the Islamic Republic of pursuing a covert weapons program, but Tehran has consistently denied the claims and says it needs nuclear energy for civilian needs.
The EU's Javier Solana said progress was made in some areas and the talks would continue next week.
"We have made progress. We want to continue that line and we are going to meet next week," Solana said.
Iran's Larijani said the meeting was constructive.
"We have made constructive progress. We have reached common points of view on a number of issues," Larijani said.
The UN Security Council adopted Resolution 1696 July 31, demanding that Iran suspend uranium enrichment by August 31 or face possible economic and diplomatic sanctions. However, an IAEA report said Tehran had refused to suspend the program and had blocked IAEA inspectors from inspecting Iran's nuclear facilities.
