April 21, 2026

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Ria Reddy, Ben Rezaei, Nidal Morrison, Avery Borens, Katherine Wells, Parker Hempel, Ben Schmida, Adham Fattah, and Brian Carter

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The United States extended its ceasefire with Iran “until such time as [the Iranian] proposal is submitted and discussions are concluded.” US President DonaldTrump stated on April 21 that Pakistani mediators urged the United States not to resume attacks while Iranian leaders work to produce a “unified proposal.” The reference to a ”unified” proposal appears to imply that previous proposals were not unified in some way, which is consistent with ISW-CTP’s assessment that one challenge with the ongoing negotiations is the divided nature of Iran’s negotiating team. The ceasefire extension comes after a second round of US–Iran negotiations scheduled for April 21 in Islamabad, Pakistan, was cancelled because Iran did not confirm its participation and did not respond to US positions. Trump confirmed that Washington will maintain its blockade of Iranian ports.

Conflicting reports on April 20 and 21 about Iran’s participation in the scheduled negotiations and Iran’s failure to produce a unified proposal reflect the ongoing intra-regime power struggle between Parliament Speaker Mohammad Bagher Ghalibaf and Islamic Revolutionary Guards Corps (IRGC) Commander Major General Ahmad Vahidi. ISW-CTP continues to assess that Vahidi appears to have the upper hand over Ghalibaf at the moment. The Wall Street Journal, citing unspecified sources, reported on April 21 that Iranian officials initially signaled that they would attend the talks but later introduced a precondition following pressure from the IRGC that the United States lift its blockade before negotiations begin. That the regime then adopted this precondition as official regime policy suggests that senior-most IRGC commander Vahidi and aligned actors currently wield significant influence on Iranian decision-making. This dynamic is consistent with reporting that Vahidi is the only senior official who maintains direct access to Mojtaba Khamenei and relays key decisions, which gives him significant power. Ghalibaf has publicly supported negotiations and has not explicitly called for preconditions. The Trump administration seems to have been willing to negotiate in talks without preconditions.

Iranian officials and IRGC-affiliated media are signaling readiness for the imminent resumption of war. IRGC-affiliated Tasnim News Agency reported on April 21 that Iran has prepared for a new phase of fighting. Tasnim added that Iran has assessed the likelihood of renewed conflict as high over the past two weeks and has conducted certain military redeployments and prepared new target lists accordingly. Iranian Judiciary Chief Gholam Hossein Mohseni Ejei separately assessed on April 21 that the likelihood of renewed US and Israeli attacks is high and emphasized the need for preparation. An unspecified senior Israeli security official told Israel’s state broadcaster on April 21 that Israel is preparing for the resumption of fighting with Iran as well. The official assessed that the United States and Iran will fail to reach any understanding and noted that Israel is ready to immediately resume the war.

• The United States extended its ceasefire with Iran “until such time as [the Iranian] proposal is submitted and discussions are concluded.” Trump confirmed that Washington will maintain its blockade of Iranian ports.

• Conflicting reports on April 20 and 21 about Iran’s participation in the scheduled negotiations and Iran’s failure to produce a unified proposal reflect the ongoing intra-regime power struggle between Parliament Speaker Mohammad Bagher Ghalibaf and Islamic Revolutionary Guards Corps (IRGC) Commander Major General Ahmad Vahidi. ISW-CTP continues to assess that Vahidi appears to have the upper hand over Ghalibaf at the moment.

• Iranian-backed Iraqi militias conducted up to half of the roughly 1,000 drone attacks targeting Saudi Arabia during the war, according to unnamed sources speaking to the Wall Street Journal on April 21. ISW-CTP previously assessed that it is very unlikely that Iranian-backed Iraqi militias would conduct drone attacks against regional states if the Iranian regime opposed such attacks, which suggests that Iran has not ordered its militia partners to cease attacking regional states.

• Hezbollah attacked Israeli forces in southern Lebanon and northern Israel for the first time since the Israel-Lebanon ceasefire took effect on April 16. The IDF struck the Hezbollah rocket launcher responsible for the attack on Israeli forces in Rab el Thalathine.

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