EU foreign policy chief Catherine Ashton pushed Iran on Thursday to move forward with stopping its nuclear programme as Israel's impatience with the ineffectiveness of sanctions grows, dpa reported.
Ashton spoke on the telephone with Iran's chief nuclear negotiator Saeid Jalili.
"I impressed the need for Iran now to address the issues we have raised in order to build confidence," Ashton said in an e-mailed statement.
Ashton's call was the latest step in a series of meetings between Iran and the so-called 5+1 nations - China, Russia, France, Britain and the US plus Germany - who suspect Iran of building a nuclear weapon and are pressing the Islamic republic to halt its nuclear enrichment activities.
Tehran insists that its nuclear programme is of a peaceful nature. Israel sees the Islamic republic as an existential threat, given repeated statements by its leaders that the Jewish state should be wiped off the map.
Feeding speculation about a possible unilateral military move against Iran, Israeli Prime Minister Benjamin Netanyahu said earlier this week that he had not yet decided whether to order an attack. Any decision to do so would be taken by the political echelon, and not by the military, he said.
Washington opposes any Israeli military action at this point, and insists that sanctions must be given more time to see their full effect. Both the European Union and the US have placed crippling bans on doing business with the country's oil industry.
On Monday, the screws were tightened even more by the White House and on Wednesday, the US Congress also imposed a new round of tougher sanctions.
Mitt Romney, the Republican who is challenging President Barack Obama for the White House in November, said in recent days that he would back Israeli unilateral military action, although the campaign backtracked a bit on the promise.
On Wednesday, US Defence Secretary Leon Panetta was in Tel Aviv trying to persuade Israel to remain patient, although he also said the United States had options other than sanctions if Iran continues its nuclear drive.
Netanyahu has repeatedly warned that sanctions, and diplomatic talks with Tehran, merely enable the Iranians to play for time while continuing their nuclear activities.
Ashton said in Thursday's statement that she and Jalili agreed to talk again "after further reflection at the end of the month."