U.S. Vice President JD Vance is expected to travel to Islamabad, Pakistan, on April 21, a day after the second round of U.S.-Iran talks were expected to take place, as the United States likely waited for some indication that Iran would participate in upcoming talks, AP reported on April 21. Iranian officials told regional mediators that Tehran would send a delegation — which is set to arrive early April 22 — after Iranian Supreme Leader Mojtaba Khamenei reportedly approved participation late on April 20.

Egypt, Pakistan and Turkey increased diplomatic pressure on Iranian officials over the past 24 hours to participate in the talks. In an April 21 X post, Iran's Parliamentary Speaker Mohammad Bagher Qalibaf said Iran is "preparing to show new cards on the battlefield" if fighting resumes. Furthermore, Iran has reportedly given its commanders more independent control over Iraqi militias, decentralizing the chain of command.