US President Joe Biden expressed hope Iran would stand down despite its threat to avenge the assassination of Hamas’ leader in Tehran, as fears mounted that Israel’s war against Palestinians in Gaza could escalate into a wider Middle East conflict.

According to The Iran Project, regional tensions have soared following the assassination of Ismail Haniyeh, Hamas' top leader, on Wednesday, a day after an Israeli strike in Beirut killed Fuad Shukr, a senior military commander from the Lebanese group Hezbollah, which like Hamas is backed by Iran.

Iran and Hamas have blamed Israel for Haniyeh’s killing, and they, together with Hezbollah, have vowed revenge. Israel has not claimed or denied responsibility.
Asked by reporters whether Iran would stand down, Biden said on Saturday in response to a shouted question, "I hope so. I don't know."
Seeking to bolster defenses in the Middle East in response to threats from Israel’s foes, the Pentagon said on Friday it would deploy additional fighter jets and Navy warships to the region.