GENEVA (AFP) - Six world powers and Iran wrapped up two days of talks in Geneva Tuesday on Tehrans contentious nuclear programme, with an agreement to meet again in Istanbul next month despite clear differences. The European Unions top diplomat Catherine Ashton told journalists they agreed to fresh talks in Istanbul to discuss practical ideas and ways of cooperating towards the resolution of our core concerns about the nuclear issue. But Irans top negotiator Saeed Jalili said barely an hour later that both sides agreed only to further talks based on cooperation in Istanbul at the end of January and that everything else was not true. The only outcome of our talks today was the agreement we reached to organise a set of talks based on cooperation... and anything other than this has no value, said Jalili, adding that additional points were a sign of disrespect. Jalili insisted that parties to the Geneva talks agreed on the final wording, and that he didnt think parties would say differently from what happened. If this happened, then that would only create a high wall of mistrust. It only took us a few minutes to come to the hotel from the conference centre, it would be regretful if within a few minutes, the wording has been changed. Jalili said that the next meeting would take place only exclusively on the basis of the wording agreed in the Geneva talks. We hope they will respect the conclusion of the meeting. As long as they respect it, the meeting will take place, he said. The Swiss organiser of talks had originally announced that Jalili would hold a joint press conference with Ashton, but finally only the Iranian was present. The Iranian nuclear negotiator would not be drawn into why Ashton cancelled. In a separate meeting with the press, Ashton did not take questions, but only read out a statement, saying that world powers recognise Irans rights, but insist it fulfils its obligations. The EUs top diplomat represented the five permanent powers of the Security Council Britain, China, France, Russia and the United States, plus Germany at the Geneva meeting. Besides holding plenaries with all parties, Jalili also met one-on-one with heads of several delegations, including Britain, China and Russia. In addition, he held a working dinner with Ashton on Monday night. However, Jalili had refused a request by the head of the US delegation, Under Secretary of State William Burns, for a bilateral meeting, a source close to the Geneva talks said. A senior US administration official said following the two-day negotiations: All expectations for these talks were low and I cant say they were exceeded. But he insisted that they were a start and that they had dealt three quarters of the time with the nuclear issue even though the discussions were difficult, candid. He underlined that suspension of enrichment is still mandated by UN Security Council resolutions and that is still the position of the P5+1 (powers). In Istanbul, the six powers would be seeking concrete steps that can be used to rebuild confidence, the official said. Iranian President Ahmadinejad called on the six powers to lift sanctions against his country if they want the talks to be fruitful. Iran is under four sets of UN sanctions over its refusal to suspend uranium enrichment, the sensitive process which can be used to make nuclear fuel or, in highly extended form, the fissile core of an atom bomb.