TYRE, Lebanon — Iran announced on Saturday that it had closed the Strait of Hormuz in response to Israeli attacks in Lebanon, warning that ongoing fighting could undermine current negotiations with the United States. The announcement came as Iranian and U.S. officials prepared to resume talks in Switzerland aimed at reaching an interim agreement.

U.S. President Donald Trump responded to the developments by threatening to impose American tolls on vessels passing through the strategic waterway if a final deal with Iran is not reached within 60 days. Trump described the tolls as payment for the United States’ role as a "Guardian Angel" to Middle Eastern countries. The existing agreement includes provisions for toll-free passage for 60 days.

The technical-level negotiations, scheduled to begin on Sunday, involve key mediators from Pakistan and Qatar, reflecting the complex regional dynamics at play. U.S. Vice President JD Vance traveled to Switzerland on Saturday evening to participate in the talks. Iranian state television simultaneously released footage of Iran's delegation arriving in Switzerland, which includes parliamentary Speaker Mohammad Bagher Qalibaf, Foreign Minister Abbas Araghchi, and senior officials from the central bank and oil sector.

The talks are centered on unfreezing billions of dollars in Iranian assets as part of the broader effort to ease nuclear tensions and regional hostilities. Although negotiations were initially planned to start on Friday, Iran postponed its participation amid escalating violence in Lebanon.

According to unnamed U.S. and regional officials, negotiators from the United States, Qatar, and Iran succeeded in facilitating a temporary agreement between Israel and Hezbollah to reduce hostilities in Lebanon. Vice President Vance expressed cautious optimism about making progress both on nuclear talks and achieving a ceasefire in southern Lebanon, stating he expected to remain in Switzerland “for a day or two.”

Iranian Foreign Ministry representatives emphasized that negotiations toward a final agreement would proceed only if key commitments by all parties were upheld. The situation underscores the fragile nature of the ongoing diplomacy, with regional security developments directly influencing the pace and scope of negotiations.