Officials from Britain, France and Germany met with an Iranian delegation in Paris on Thursday and Friday, and stressed their wish to see a halt to Iran's work on the sensitive nuclear fuel cycle.
"Each side repeated their positions, and there were no changes," said a diplomat from one of the three European states.
"We would like Iran to stop nuclear fuel cycle work, but Iran sees its suspension as just a temporary measure. Therefore, no substantial progress was made," the source told AFP.
"This is disappointing, but having said that, nobody was honestly expecting a breakthrough," the diplomat added. "The meeting was more aimed at keeping up contacts."
Iran announced Saturday it had resumed making parts for centrifuges used for enriching uranium, blaming the Europeans for being critical at the International Atomic Energy Agency (IAEA).
Although Foreign Minister Kamal Kharazi asserted that Iran was committed to a temporary suspension of enrichment, he did say "no country has the right to deprive us of nuclear technology".
Under an agreement reached last year with Britain, France and Germany, Iran had agreed to suspend sensitive uranium enrichment, allow tougher inspections and file a comprehensive declaration of its nuclear activities.
The measures were aimed at "building confidence" while the IAEA conducted a major probe of Iran's bid to generate electricity through nuclear power, seen by the United States as a cover for secret weapons development.
But since then, experts from the UN's nuclear watchdog have found omissions in Iran's reporting, inspection visits have been delayed and the regime has backed away from a pledge to suspend all enrichment-related activities.
Ideally, the Europeans would like to see Iran cease its work on the nuclear fuel cycle altogether, even if such work is permitted under the nuclear Non-Proliferation Treaty (NPT).
The concern is that once fully mastered, a country possessing such technology can easily divert it into military usage - a loophole in the treaty.
Many diplomats believe that even if Iran may not be working on nuclear weapons now, it would like to have the option in the future. And operating a full fuel cycle in full view of the IAEA is the easiest and "most legal" way to go about this.
Iran denies it is seeking nuclear weapons, but insists on its legal right to master the fuel cycle for power generation. Being dependent on outside sources for nuclear fuel, Iran says, is not an option.
During the Paris talks, "the Iranian side insisted on pushing ahead with work such as enrichment. They are still sticking to a suspension, but say they wish to resume as soon as is possible," said another diplomat close to the discussions.