The security aid package the United States has refused to give Israel for the past few months out of concern that Israel would use it to attack nuclear facilities in Iran included a large number of "bunker-buster" bombs, permission to use an air corridor to Iran, an advanced technological system and refueling planes.

Officials from both countries have been discussing the Israeli requests over the past few months. Their rejection would make it very difficult for Israel to attack Iran, if such a decision is made.

About a month ago, Haaretz reported that the Bush administration had turned down an Israeli request for certain security items that could upgrade Israel's capability to attack Iran. The U.S. administration reportedly saw the request as a sign preparations were moving ahead for an Israeli attack on Iran.

Diplomatic and security sources indicated to Haaretz that the list of components Israel included:

Bunker-buster GBU-28 bombs: In 2005, the U.S. said it was supplying these bombs to Israel. In August 2006, The New York Times reported that the U.S. had expedited the dispatch of additional bombs at the height of the Second Lebanon War. The bombs, which weigh 2.2 tons each, can penetrate six meters of reinforced concrete. Israel appears to have asked for a relatively large number of additional bunker-busters, and was turned down.

Air-space authorization: An attack on Iran would apparently require passage through Iraqi air space. For this to occur, an air corridor would be needed that Israeli fighter jets could cross without being targeted by American planes or anti-aircraft missiles. The Americans also turned down this request. According to one account, to avoid the issue, the Americans told the Israelis to ask Iraqi Prime Minister Nuri al-Maliki for permission, along the lines of "If you want, coordinate with him."

Refueling planes. An air attack on Iran would require refueling of fighter jets on the way back. According to a report on Channel 10 a few weeks ago, the U.S. rejected an Israeli request for more advanced refueling tankers, of the Boeing 767 model.

The refueling craft the Israel Air Force now uses are very outmoded, something that make it difficult to operate at long distances from Israel. Even if the Americans were to respond favorably to such a request, the process could take a few years.

The IDF recently reported that it is overhauling a Boeing 707 that previously served as the prime minister's plane to serve as a refueling aircraft.

Advanced technological systems. The Israeli sources declined to give any details on this point.

The Israeli requests were discussed during President George W. Bush's visit to Israel in May, as well as during Defense Minister Ehud Barak's visit to Washington in July. In a series of meetings at a very senior level, following Bush's visit, the Americans made clear to the Israelis that for now they are sticking to the diplomatic option to halt the Iranian nuclear project and that Jerusalem does not have a green light from Washington for an attack on Iran.

However, it appears that in compensation for turning down Israel's "offensive" requests, the U.S. has agreed to strengthen its defensive systems.

During the Barak visit, it was agreed that an advanced U.S. radar system would be stationed in the Negev, and the order to send it was made at that time. The system would double to 2,000 kilometers the range of identification of missiles launched from the direction of Iran, and would be connected to an American early warning system.

The system is to be operated by American civilians as well as two American soldiers. This would be the first permanent U.S. force on Israeli soil.

A senior security official said the Americans were preparing "with the greatest speed" to make good on their promise, and the systems could be installed within a month.

The Israeli security source said he believed Washington was moving ahead quickly on the request because it considered it very important to restrain Israel at this time.

At the beginning of the year, the Israeli leadership still considered it a reasonable possibility that Bush would decide to attack Iran before the end of his term.

Prime Minister Ehud Olmert, in private discussions, even raised the possibility that the U.S. was considering an attack in the transition period between the election in November and the inauguration of the new president in January 2009.

However, Jerusalem now assumes that likelihood of this possibility is close to nil, and that Bush will use the rest of his time in office to strengthen what he defines as the Iraqi achievement, following the relative success of American efforts there over the past year and a half.