The Israeli request for M-26 artillery rockets, which are fired in barrages and carry hundreds of grenade-like bomblets that scatter and explode over a broad area, is likely to be approved shortly, the New York Times reported on Friday.
The US Defence Department, without confirming or denying the report, said "We fully support Israel's right to defend itself."
Israel was authorized to buy the multiple launch rocket system in 1995, said Commander Greg Hicks, a Pentagon spokesman.
"These are not indiscriminate arms transfers," Hicks said. They are done "in the interest of peace and broader international security" and "help peaceful nations meet their legitimate needs of self-defense," he said.
At least 10 other countries including Egypt and Bahrain have also bought the missile system, manufactured by Lockheed Martin, he said.
But some State Department officials want to delay the approval because the rockets could cause civilian casualties if used against targets in populated areas of southern Lebanon, the New York Times reported.
Israel hit back at Hezbollah only after repeatedly warning the civilian population to vacate the area, said David Siegel, a spokesman for the Israeli embassy in Washington.
"It's important to stress that Hezbollah operates from densely populated areas in attacking Israeli civilian targets and that Israel, in defending itself, uses only precision-guided munitions," he said.
Israel needed the rockets immediately the New York Times quoted officials as saying, because it has been unable to suppress Hezbollah's Katyusha rocket attacks by using bombs dropped from aircraft and other types of artillery.
On July 14, the Bush administration supported an Israeli request for JP-8 jet fuel worth up to $210 million to help Israeli aircraft "keep peace and security in the region."