President Joe Biden is weighing more U.S. defenses in the Middle East as the U.S. prepares for an Iranian retaliation against Israel that officials say could include an attack on American forces.In a phone call with Israeli Prime Minister Benjamin Netanyahu Thursday, Biden said the U.S. would "support Israel's defense against threats," which would include "new defensive U.S. military deployments," according to a readout of the call.The statement did not detail what new deployments would occur ahead of an anticipated Iranian attack in response to the assassination of Hamas leader Ismail Haniyeh in Tehran.Related video above: Iran vows revenge after top militant leaders' deaths, raising fears of wider conflict According to several U.S. officials, the Pentagon has discussed with U.S. Central Command what adjustments to make to U.S. force posture in the region, but no final decision had been made as of Thursday afternoon. The officials said an Iranian response could occur in the coming days.The USS Theodore Roosevelt carrier strike group, which includes the aircraft carrier, destroyers and other warships, has been operating in the Gulf of Oman in recent weeks. The strike group could potentially move into the Gulf of Aden or the Red Sea, where Navy warships have intercepted dozens of Houthi launches over the past several months.The USS Wasp amphibious assault ship and several other Navy vessels are currently operating in the Mediterranean Sea. The group includes a Marine expeditionary unit capable of carrying out an evacuation of American citizens from Lebanon if the U.S. ordered such an evacuation.Iran's Islamic Revolutionary Guard Corps (IRGC) promised a "harsh" and "painful" response to the assassination. Israel has not commented on the killing.The Iranian response to the killing of Haniyeh may include attacks on U.S. forces in Iraq and Syria from Iranian-backed proxy militias in the region, according to the officials. For months, the militias launched scores of attacks on U.S. forces in the Middle East, but those largely subsided after a drone attack killed three U.S. service members in Jordan in January. Officials say Iran could instruct those groups to start firing on U.S. forces once again.Israel Defense Forces spokesman Rear Adm. Daniel Hagari said that "international partners" have bolstered their forces in the region, though he did not specify which countries."We have very good defense systems," he said of Israel's own preparations for an attack, "and in addition, we have international partners who have reinforced their forces in the region to help us counter the threats."A Defense Department spokesman said Thursday the Pentagon has no information to provide on the movement of U.S. forces or changes to force conditions at this time.The U.S. is expecting the anticipated Iranian attack may be similar to the barrage of ballistic missiles and drones launched against Israel on April 13, officials said. However, this attack could be larger and more complicated than before, including the possibility of a coordinated attack with Iranian proxies from multiple directions.A coalition of countries, including Jordan and other Arab states, came together in April to share intelligence and intercept the Iranian barrage. But officials say it's unclear if such a coalition could be stood up again so quickly and whether all of the countries are willing to participate once again.Hezbollah leader Hassan Nasrallah hinted that a coordinated attack on Israel could be in the works after Israel assassinated one of its top commanders in Beirut less than 24 hours before the killing of Haniyeh."Because they have picked a fight with everyone, they don't know where the response will come from … the response will come separately or coordinated," he said in a speech Thursday.The U.S. still believes that no one in the region is interested in an all-out war engulfing the Middle East, officials say, but a potential miscalculation risks sparking a broader conflict.