"Iran, of course, is a sore spot. Some sort of decision on it should be taken soon. It will probably be taken closer to the summer," Chief of Staff General Nikolai Makarov was quoted as saying by the RIA Novosti news agency.

Makarov provided no further comment and it was not immediately clear if he was referring to possible military action or future sanctions.

Russia has backed four rounds of United Nations sanctions against Iran over its nuclear programme amid growing international concern that it was pursuing military aims. But Moscow has sternly warned against using military action.

Russia last month accused Western powers of trying to "suffocate" the Iranian economy and incite popular discontent with new sanctions such as the impending oil embargo by EU states.

Shalom raised the issue with UN Secretary General Ban Ki-moon during talks that also touched on the escalating violence in Syria and the impasse in efforts to resolve the Israeli-Palestinian conflict.

"Israel believes the Iranians should stop their nuclear program and should do it immediately," Shalom told a press conference.

He hailed the recent moves by the United States and the European Union to ramp up sanctions against the Islamic republic, which the West and Israel suspects is trying to produce a nuclear bomb despite Tehran's repeated denials.

"We would like to believe that these sanctions, if they are tough enough, will bring the Iranians maybe to give up" their disputed atomic program, Shalom said.

He sidestepped several questions on whether Israel is planning a pre-emptive strike on Iran's nuclear installations.

Shalom said Ban said he was shocked by the attacks targeting Israeli embassy staff in India and Georgia on Monday, and pointed the finger of blame at Iran.

"We know that Iran and its collaborators are behind that attack," he said, adding that Israel would "continue to cooperate with the governments and the security forces" abroad to ensure the safety of Israeli citizens.

Embassy cars were attacked in New Delhi and Tbilisi, which left an Israeli woman diplomat critically injured in the Indian capital. In Georgia, the bomb was dismantled before it exploded.

Then on Tuesday, a suspected Iranian bomber had his legs blown off as he hurled a grenade at Thai police, officials said. Israel also accused Tehran of being behind that attack.