Annika Ganzeveld, Ashka Jhaveri, Kelly Campa, Johanna Moore, Alexandra Braverman, and Brian Carter

Information Cutoff: 2:00 pm ET

The Iranian Assembly of Experts elected its leadership board on May 21, marking a new era for the body responsible for selecting the next supreme leader. The Assembly of Experts is an Iranian regime entity constitutionally responsible for monitoring the supreme leader and selecting his successor. Assembly of Experts leadership board members serve two-year terms. This is the first time since 2016 that the Assembly of Experts has not been led by influential cleric Ayatollah Ahmad Jannati.

US Chairman of the Joint Chiefs of Staff Gen. Charles Brown Jr. said on May 20 that Israel’s strategy in the northern Gaza Strip is making “achieving lasting stability more difficult.” Brown said that Israel has not been holding territory after conducting clearing operations, which allows Hamas to return to those areas. Israeli officials, including the IDF chief of staff, have criticized Israels current operational concept because it lacks a clear post-war plan’. CTP-ISW has previously observed that Hamas has exploited Israeli withdrawals from the northern Gaza Strip to begin reconstituting there.

The IDF engaged Palestinian fighters in eastern Rafah on May 21. The IDF Givati Brigade detained three Palestinian fighters who emerged from a tunnel in the area. The IDF also confirmed that the Nahal Brigade is operating in Rafah. The Nahal Brigade captured a tunnel shaft where Palestinian militias had stored RPGs, grenades, and other explosive devices. The IDF currently has five brigades operating in Rafah. A Palestinian journalist reported on May 21 that Israeli forces have not made any advances into urban areas of Rafah but are advancing along the Philadelphi Corridor. Two Palestinian militias mortared Israeli forces operating in eastern Rafah.

US National Security Advisor Jake Sullivan presented a proposal for ending the war to senior Israeli officials during his visit to Israel on May 19. An Israeli journalist cited unspecified officials who said that the proposal includes a path to normalization with Saudi Arabia, an expanded regional security architecture to counter Iran that includes regional countries and the United States, funds to invest in the Gaza Strip, a deal for the release of hostages, and the promotion of a political agreement with Lebanese Hezbollah on Israel’s northern border. Israel would be required to end the war, declare plans to pursue a political solution for Palestine, and agree on a mechanism for managing the Gaza Strip that does not involve Hamas or a military government. The sources said Israeli Prime Minister Benjamin Netanyahu did not say “no” to the proposal, but the two sides did not agree on unspecified details. The US proposal states that Hamas cannot govern the Gaza Strip but fails to explain how the United States or Israel could ensure that outcome. Hamas has already attempted to reassert its governing authority during the war, especially in the northern Gaza Strip.

US Secretary of State Antony Blinken said on May 21 that Israel will need to decide if it will agree to end the war in the Gaza Strip and take part in a “credible pathway to a Palestinian state” to normalize relations with Saudi Arabia. Saudi Arabia has conditioned normalization with Israel on a path to Palestinian statehood. Blinken said that bilateral agreements between the United States and Saudi Arabia would be worked out “relatively quick given all the work that’s been done.”

Key Takeaways:

• Iran: The Iranian Assembly of Experts elected its leadership board on May 21, marking a new era for the body responsible for selecting the next supreme leader. This election is particularly important given the supreme leader’s age (84) and the recent death of the Iranian president. The assembly formally chooses the supreme leader and informally influences supreme leader succession.

• Gaza Strip: The US Chairman of the Joint Chiefs of Staff said that the IDF’s failure to hold territory after clearing it is allowing Hamas to return to previously cleared areas.



• Humanitarian Aid: The United States said that no humanitarian aid from the US-constructed temporary pier in the central Gaza Strip has reached the broader Palestinian population.

• West Bank: The IDF intentionally detonated a vehicle-borne improvised explosive device on May 20 in Tubas.

• Southern Lebanon and Golan Heights: The IDF intercepted a “suspicious aerial target” over Syria before it entered Israeli territory.

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ISW–CTP has launched an interactive map of Israeli ground operations to accompany our daily campaign assessments of the Israel–Hamas war. This product complements the daily static maps that ISW-CTP produces with high-fidelity and, where possible, street-level assessments of the war in Israel.

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