A Washington Post columnist, David Ignatius, reported on Thursday that the U.S. Defense Secretary Leon Panetta “believes there is a strong likelihood that Israel will strike Iran in April, May or June,” before Iran acquires the capability to produce a fully-fledged nuclear bomb.

"The Israelis fear that Iran will have stored enough enriched uranium in deep underground facilities to make a weapon very soon and only the United States could then stop them militarily," Ignatius wrote.

CNN confirmed the Washington Post journalist’s report citing an unknown senior U.S. administration official.

Ignatius wrote that one of the signals of the upcoming military operation against Iran was a statement by the Israeli Defense Minister Ehud Barak last month who said that the United States and Israel should postpone a military exercise that would have taken place in May.

Panetta and the Pentagon refused to comment on the Washington Post report, Reuters said.

Israel views Iran's uranium enrichment activity as a major threat to its security regardless of the fact that the Islamic republic denied that its nuclear program is not for military use, it claims it needs nuclear power to supply a growing demand for electricity.

Israeli Military Intelligence Head, Maj. Gen. Aviv Kochavi said on Thursday that Iran had over four tons of enriched materials and nearly 100 kilograms of 20-percent enriched uranium, which is enough for producing four nuclear bombs.

In late January the EU approved an introduction of the embargo on Iranian oil exports. Iran in response threatened to block the Strait of Hormuz, a major export route for oil supplies from the Middle East.