Geneva: Iran’s talks with six global powers on a long-term deal to curb its nuclear programme in exchange for an end to sanctions could be extended for another six months if no deal is reached by a July 20 deadline, a senior Iranian official said on Monday.

The four-month-old round of negotiations ran into difficulty last month with each side accusing the other of making unrealistic demands, sowing doubt about prospects for a breakthrough next month.

Western officials say Iran wants to maintain a uranium enrichment capability far beyond what is suitable for a civilian nuclear energy programme. Iran says it wants to avoid reliance on foreign suppliers of fuel for its nuclear reactors and rejects Western allegations it seeks the capability to make nuclear weapons under the guise of a peaceful energy programme.

Deputy Foreign Minister Abbas Araqchi spoke of a possible extension to the talks in remarks in Geneva to Iranian media on the sidelines of meetings with senior US officials and the European Union’s deputy chief negotiator.

“We hope to reach a final agreement [by July 20] but, if this doesn’t happen, then we have no choice but to extend the Geneva deal for six more months while we continue negotiations,” Araqchi was quoted as saying by Iran’s state news agency Irna.

“It’s still too early to judge whether an extension will be needed. This hope still exists that we will be able to reach a final agreement by the end of the six months on July 20.” The United States said on Saturday it would send its No. 2 diplomat, Deputy Secretary of State Bill Burns, to Geneva to meet a delegation led by Araqchi.

Burns led secret US-Iranian negotiations that helped bring about an interim nuclear agreement between Iran and the major powers on November 24, allaying fears of war over the dispute.

Under Secretary of State Wendy Sherman, the primary US negotiator with Iran, is accompanying him on a team that includes senior White House national security staff.

The US decision to travel to Geneva and meet with the Iranian delegation appeared to reflect a desire to try to break the deadlock in the Vienna negotiations.

“There are still gaps between Iran and the [six powers] in various issues and in order to bring our views closer, the other side must make tough decisions,” Araqchi said.

“The goal of these negotiations was to secure the Iranian nation’s rights in the nuclear issue for peaceful purposes,” he was quoted as saying. “We hope that we will be able to achieve this in the remaining time under the six-month nuclear deal.” Another senior Iranian official, Takht Ravanchi, was quoted as saying that putting an end to sanctions was one of the issues discussed during the bilateral session with the Americans.

Iran, the United States, Britain, France, Germany, Russia and China included the July 20 deadline to reach a comprehensive agreement in the text of the November 24 preliminary deal.

That pact, under which Iran shelved some sensitive nuclear activities in exchange for limited relief from sanctions, gave scope for a six-month extension if needed to nail down a final settlement that would end sanctions and remove the threat of war.

An extension would allow up to half a year more for limited sanctions relief and restraints on Iranian nuclear work as agreed in Geneva.

To avoid open conflict with the US Congress, where hawkish lawmakers prefer the stick to the carrot in dealing with Iran, Obama would want their approval to extend sanctions relief.

EU foreign policy chief Catherine Ashton is coordinating the six powers’ talks with Tehran. Her deputy Helga Schmid is currently in Geneva for the bilateral meetings with Iran ahead of the next round of Vienna talks scheduled for June 16-20.

Separately, in a shift of tone from Prime Minister Benjamin Netanyahu’s scepticism, a senior Israeli intelligence officer said on Monday that Iran was negotiating seriously on a deal to limit its disputed nuclear programme.

Brigadier-General Itai Brun, military intelligence’s chief analyst, told a strategic forum that Iran was honouring the November interim agreement that Netanyahu had condemned as an “historic mistake” for easing sanctions on Israel’s arch-enemy.