JERUSALEM — Israel’s top leadership has spent the week answering and evading questions about widespread reports that it is once again considering a strike on Iran’s nuclear complexes, while President Obama said Thursday that he and his allies would maintain “unprecedented international pressure” on Tehran to keep it from producing a nuclear weapon.

Israeli officials would not confirm or deny multiple reports in the Israeli news media that Prime Minister Benjamin Netanyahu and Defense Minister Ehud Barak were pressing for a decision on whether and when to strike a uranium enrichment facility at Natanz, the centerpiece of Iran’s known nuclear-fuel production, and related sites across the country.

Several Israeli ministers have publicly placed blame for the leaks on Meir Dagan, the former chief of Israel’s Mossad intelligence service, who after leaving office this year said that Mr. Netanyahu was intent on launching such an attack, and had to be restrained by opposition from top intelligence and military officials, almost all of whom have since left office.

Mr. Dagan, who is believed to have played a central role in unleashing the Stuxnet computer worm that set back Iran’s nuclear efforts by disabling about a fifth of its nuclear centrifuges, has argued that military action is unlikely to do enough damage and could set off a new war in the Middle East.