The U.S. and its allies are bracing for a potential Iranian attack on Israel this week, following the assassinations of senior Hamas and Hezbollah leaders. In response, the U.S. has increased its military presence in the Middle East, deploying the USS Abraham Lincoln aircraft carrier strike group and a guided missile submarine to the region. White House national security spokesman John Kirby expressed concerns about imminent retaliatory strikes, emphasizing that the U.S. is prepared to defend Israel if necessary. The Biden administration is actively engaging with European allies to de-escalate tensions and push for a ceasefire between Israel and Hamas. Hamas has demanded adherence to a previously agreed proposal rather than new negotiation rounds. Regional leaders, including those from the U.S., UK, France, Germany, and Italy, have called for Iran to cease its threats, warning of severe consequences for regional security if an attack occurs.