WASHINGTON: US troops have arrived in Israel as part of the deployment of a missile defence battery, the Pentagon said on Tuesday, a move that will help protect Washington`s ally but deepens the United States` involvement in the conflict.

The deployment of the Terminal High Altitude Area Defence (THAAD) system comes as Israel prepares to hit back against Iran for a major ballistic missile attack earlier this month, and the battery will boost Israeli defences in case Tehran strikes back again.

Israel has targeted leaders of Hezbollah and Hamas since October last year, and has been accused of killing Hamas`s political chief on Iranian soil, which Tehran cited as part of its justification for its Oct 1 strikes.

US ships and warplanes have helped defend Israel from the Iranian attacks, but deployment of the battery will put the roughly 100 US troops who will operate it as well as the system itself on the ground in Israel and more directly in harm`s way.`Putting US service members in Israel proper shows that Washington is very visibly and tangibly committed to Israel`s se curity and will fight if necessary,` said Raphael Cohen, a senior political scientist at the Rand Corporation.

President Joe Biden`s administration `likely hopes that this move will increase the deterrence vis-a-vis Iran and reassure the Israelis`, he added.

Cohen said the move may give the Biden administration greater leverage to shape the Israeli response to the Iranian strikes.

`Very expensive target` `Particularly if Iran increases its volume of fire and Hezbollah continues to attack, more missiles will get through and hit their targets,` he said, referring to the Lebanonbased group that Israel has launched a renewed military offensive on since last month.

`The battery will be fully operational capable in the near future, Pentagon spokesman Major General Pat Ryder said in a statement.-AFP