Sides in the ongoing Iranian nuclear talks are discussing the plan of shipping Iran's low enriched uranium (LEU) stockpile to Russia, while gaps remain in inspection of Iran's military sites and re-imposing of sanctions, diplomatic sources told Xinhua on Saturday.
The sources said shipping the LEU out of Iran "is not a problem any more" and the plan of shipping the enriched uranium to Russia are still being discussed in the intensive talks.
Handling of Iran's fissile materials is one of the Western's core concerns over Tehran's nuclear plan, as technically, possession of large enriched uranium stockpile will allow Iran to be able to make a nuclear bomb in a relatively short time.
According to a recent International Atomic Energy Agency (IAEA) report, Iran owns 7,537 kg LEU stockpile in end-June.
Western nations had previously asked Iran to ship its nuclear materials out of the country, but Tehran rejected the proposal.
In the framework deal agreed in Lausanne, Iran will reduce its stockpile of all the LEU to 300 kg of 3.67 percent LEU for 15 years, but the framework failed to specify by which means Iran will be able to reduce the stockpile.
The sources said sides are still negotiating about whether to strengthen the Additional Protocol in the text of the deal, indicating that gaps remain in the military site inspection as to whether inspectors would be granted the right of having full access to some allegedly suspicious facilities and locations of the country.
American officials said last year that the provisions of the Additional Protocol were not adequate in the case of a country that, like Iran, "has built a series of secret facilities", and that they would press for a far more intrusive set of inspection rules.
Just days before the latest round of nuclear talks started in Vienna, Iranian supreme leader Ayatollah Khamenei expressed firm opposition to "unconventional inspections, questioning Iranian figures, and the inspection of military sites" as among the red lines for the country.
Iran is still defending its "red line" of not giving the UN inspectors access to its military sites.
But the diplomatic sources told Xinhua Saturday that the Iran has accepted the Additional Protocol to grant the inspectors wider access to its nuclear activities.
A senior western official earlier this week said with the Safeguards Agreement and the Additional protocol, if the "IAEA believes that it needs access and has a reason for that access, then we have a process to ensure that that access is given."
Iran and the five United Nations Security Council permanent members plus Germany have been negotiating over the past 16 moths to reach a long-term deal over Tehran's controversial atomic plan.
During the period, Iran would suspend some sensitive nuclear activates, in return, Western nations would partially relieve some sanctions imposed on Tehran.
According to the source that discussion on the "automatic re-imposing" of the sanctions on Iran is still ongoing, indicating gaps remain over the issue.
U.S. and European Union's nuclear-related sanctions against Tehran will be suspended after the IAEA has verified that Iran has taken all of its key nuclear-related steps. If at any time Iran fails to fulfill its commitments, these sanctions will snap back into place.
UN Security Council and Western states imposed tough sanctions on Iran, which is crippling the country's economy, Iran demands western states to relief the sanctions as soon as the deal is agreed.
On Thursday, Russia's top negotiator Sergei Ryabkov voiced cautious optimism, saying a complex text and annexes were "91 percent" finished.
According to the sources, the draft of the text of deal with five annexes is quite complicated, with each annex specifying a key area of the Iranian nuclear issue, including sanction relief, action plan, nuclear cooperation, the committee of the monitoring of the implementation, and limitation of Iran's nuclear plan.
The draft deal after being agreed on by all sides in the talks needs to be endorsed by UN Security Council resolution, and the period before the comprehensive deal is started to be implemented by all sides could be around half a year, the sources said.
The deadline for sides to reach the deal had been extended from June 30 to July 7.
International Atomic Energy Agency (IAEA) Director General Yukiya Amano met with Iranian president Hassan Rohani and other top Iranian officials on Thursday, saying that both sides "have a better understanding on some ways forward."
In a report released in November 2011, IAEA said based on "credible information" it obtained, Iran might have carried out nuclear weapon program, so-called Possible Military Dimensions (PMDs) under cover of its civilian power plan, which Tehran denied.
The sources said there could be an agreement over the timetable of resolving the PMD issue.
"With cooperation from Iran I think we can issue a report by the end of the year on the assessment of the clarification of the issues related to the possible military dimensions," IAEA Director General Yukiya Amano said on Saturday.
Iran had been asked by powers to answer the questions of its past nuclear activities so as to address IAEA's concern, but by which mean should Iran clarify its past suspicious plan was not specified.