Israeli President Shimon Peres warned on Thursday that the Jewish state is keeping "all options" on the table on the issue of Iran's nuclear activities.

"The state of Israel is a sovereign state; it has the right and capacity to defend (itself) against any threat," the Israeli leader said in remarks broadcast on military radio.

"When we say that all options are on the table, we really mean it," he added.

Peres, who made the remarks in an address to a meeting of the Conference of Presidents grouping US Jewish groups, denied a front page report in Israeli newspaper Haaretz on Thursday that he was opposed to an attack on Iran.

The report said that Peres would tell US President Barack Obama on a visit next month that he was opposed to an Israeli attack on Iran in the near future.

"As far as I'm concerned I never in my life told anybody before a meeting with such a leader what I'm going to tell him," he said.

Peres's comments come amid continuing speculation about the possibility of an Israeli strike on Iran, which much of the international community believes is using its nuclear programme to mask a weapons drive.

Tehran denies those charges, saying its nuclear programme is for peaceful medical and energy purposes only.

But the international community has imposed increasingly tough sanctions on Iran and Israel has regularly warned that it retains the option of a military strike against the Islamic Republic's nuclear facilities.

IAEA to explain 'failed' Iran mission: diplomats
Vienna (AFP) Feb 24, 2012 - UN atomic agency chief Yukiya Amano is expected to outline in a report Friday why its team investigating Iran's suspected nuclear weapons drive returned empty handed this week, diplomats said.

IAEA chief inspector Herman Nackaerts and his team returned from Tehran on Wednesday with no progress in their search for answers from Iran on its alleged bid to develop nuclear weapons, leading Washington to brand the trip a "failure."

It also threw into question the possible resumption of talks between Iran and world powers that Tehran had signalled only last week it was ready for.

Diplomats in Vienna said they have begun discussing what action the 35-member IAEA board will take when it holds its next regular meeting on March 5.

In theory it could pass a resolution condemning Iran and reporting the Islamic republic to the UN Security Council, which has already passed four rounds of sanctions.

This though depends on Russia and China, which have hitherto been more lenient on Iran that their Western counterparts in the UN Security Council.

Diplomats also say that the International Atomic Energy Agency report will give an update on Iran's progress in fitting out its new facility at Fordo, near Qom, enriching uranium to 20-percent purity.

The facility, under a mountain and kept secret by Iran until late 2009, would slash the time needed to convert Iran's stockpile of low-enriched uranium to the 90-percent purity needed for a nuclear bomb if it decided to do so, experts say.

How quickly Iran could enrich would also depend on what kind of centrifuges are installed at Fordo.

Indications so far are that Iran is installing "IR-1" older-generation devices, diplomats said, which could be converted to enrich to 90 percent, but which would do the work more slowly than more state-of-the-art models.

One Western diplomat said he expected the IAEA to say that Iran had installed "high hundreds" of centrifuges at Fordo -- but not the "thousands" that have been speculated -- and of the older kind.

"The newer-generation centrifuges that they have been working on have all been at Natanz," Iran's main enrichment site, another diplomat told AFP.

"They are fewer in number, have been problematic, and we haven't heard from the IAEA that they have moved anything to Fordo."