TEL AVIV – U.S. forces are arriving in Israel in preparation for Juniper Cobra, a major joint military drill launching next week that will simulate a war in which the Jewish state comes under attack with thousands of missiles.

The ninth biennial military exercise will simulate rocket and missile attacks from both the northern borders with Lebanon and Syria and the southern border with Gaza.

Iranian proxy Hezbollah is estimated to have some 50,000 soldiers and a weapons cache of about 130,000 short-, medium- and long-range missiles.

Defense Minister Avigdor Liberman said Wednesday that should war erupt again with Lebanon, Beirut would “pay the full price” for Iranian entrenchment in the country, and “if citizens of Tel Aviv are forced to sit in shelters, all of Beirut will too.”

He added that Hezbollah has “sacrificed Lebanon’s national interests by subjugating fully to Iran.”

“Lebanon’s army and Hezbollah are the same — they will all pay the full price in the event of an escalation,” Liberman said.

Hezbollah has reportedly threatened to fire on Israel if the construction of a border fence is not stopped.

More than 3,000 soldiers from the IDF and United State’s European Command (EUCOM) take part in the biennial drill that aims to strengthen military cooperation against regional threats as well as bolster long-term security. 2016’s drill was America’s “premier exercise in this region and EUCOM’s highest priority exercise in 2016,” according to Lt. Gen. Timothy Ray, head of the U.S. Third Air Force.

“This exercise increases our military readiness, but just as importantly it also signals our resolve to support Israel.”

Earlier this week, Prime Minister Benjamin Netanyahu told Russian President Vladimir Putin that Israel would “stop” Iran if it continues to entrench itself in Syria and turns Lebanon into a “missile factory.”

The prime minister said Lebanon “is becoming a factory for precision-guided missiles that threaten Israel. These missiles pose a grave threat to Israel, and we cannot accept this threat.”

Meanwhile, the U.S. military failed to destroy a test missile off the coast of Hawaii on Wednesday, in an exercise designed to intercept ballistic missiles.

The test shoot on the island where the SM-3 Block IIA missile – co-developed by the U.S. and Japan – was designed was intended to prepare for threats from North Korea, local reports said. Another test failed in June of last year.

“The Missile Defense Agency and the U.S. Navy sailors manning the Aegis Ashore Missile Defense Test Complex conducted a live-fire missile flight test using a Standard-Missile (SM)-3 Block IIA missile launched from the Pacific Missile Range Facility, Kauai, Hawaii, Wednesday morning,” Mark Wright, a spokesman from the Missile Defense Agency, said.