The briefing for Sunday, April 19.

Iran's Islamic Revolutionary Guard Corps announced Saturday it is closing the Strait of Hormuz to commercial vessels again, threatening to target any approaching ship. The closure came as reports emerged that Iranian forces had fired on multiple vessels attempting to transit the strait, including two India-flagged merchant ships and a tanker struck by Iranian gunboats. According to the UK Maritime Trade Operations center, a container ship was also hit by an unknown projectile off Oman's northeastern coast.

The reversal occurred less than 24 hours after Iran's foreign minister announced the critical waterway had been temporarily reopened following a 10-day ceasefire between Israel and Hezbollah in Lebanon. The IRGC blamed the continued U.S. blockade of Iranian ports for the closure, stating that "approaching the Strait of Hormuz will be considered co-operation with the enemy." Iran's parliamentary speaker Mohammed Bagher Qalibaf declared in a televised interview that "it is impossible for others to pass through the Strait of Hormuz while we cannot."

President Trump said Iran cannot "blackmail" the U.S. with threats over the waterway and confirmed the U.S. naval blockade of Iranian ports will continue until a peace deal is reached. The two-week ceasefire is set to expire Wednesday, April 22. About 20% of the world's oil and liquefied natural gas normally passes through the strait, and its effective closure for nearly two months has pushed oil prices above $100 per barrel at points. Iran's Supreme National Security Council said it had received new proposals from the U.S. and was reviewing them, with Pakistani mediators working to arrange another round of negotiations before the ceasefire expires.

President Trump signed an executive order Saturday directing his administration to accelerate FDA reviews of certain psychedelic drugs, including ibogaine, a substance derived from a West African shrub that has been embraced by veterans despite known cardiac risks. The order aims to speed access to potential treatments for conditions like PTSD, severe depression, and opioid addiction, with Trump stating it will help "dramatically accelerate" access for people "suffering from debilitating symptoms."

The FDA will issue national priority vouchers next week for three psychedelics, allowing approved drugs to be reviewed in weeks rather than months—the first time the agency has offered such fast-tracking for any psychedelics. The FDA is also clearing the way for the first-ever U.S. human trials of ibogaine. However, the National Institutes of Health previously discontinued ibogaine research in the 1990s due to the drug's "cardiovascular toxicity," which can trigger potentially fatal heart problems.

The announcement surprised many researchers in the psychedelic field. Frederick Barrett, director of the Johns Hopkins Center for Psychedelic and Consciousness Research, noted that "it's been incredibly difficult to study ibogaine in the U.S. because of its known cardiotoxicity." Trump was joined in the Oval Office by Health Secretary Robert F. Kennedy Jr., podcaster Joe Rogan, and former Navy SEAL Marcus Luttrell, who credited ibogaine with changing his life. No psychedelic has been approved in the U.S., though several are being studied in large trials, and all remain classified as Schedule I substances alongside heroin.

North Korea fired multiple short-range ballistic missiles toward the sea Sunday from the Sinpo area, with each traveling approximately 140 kilometers toward the country's eastern waters, according to South Korea's Joint Chiefs of Staff. The launches occurred hours before South Korean President Lee Jae Myung departed for visits to India and Vietnam. Both U.S. and Japanese militaries detected the launches, with Japan's Defense Ministry issuing a strong protest to Pyongyang.

Sinpo is an eastern coastal city where North Korea maintains a major submarine-building shipyard. South Korea's military is analyzing whether the missiles were launched from a submarine, a land-based launcher, or both platforms. If submarine-launched, this would mark North Korea's first such test in four years—a concerning development since underwater launches are difficult for adversaries to detect in advance. North Korea unveiled a nuclear-powered submarine under construction last year.

The launches came just days after International Atomic Energy Agency Director General Rafael Grossi warned that his agency has confirmed "a rapid increase" in activities at North Korea's nuclear manufacturing facilities, pointing to "a very serious increase" in its nuclear weapons production capabilities. The tests continue North Korea's pattern of weapons demonstrations this year, including recent examinations of ballistic missiles with cluster-bomb warheads. Some observers suggest the testing is meant to increase North Korea's leverage ahead of President Trump's scheduled May summit with Chinese President Xi Jinping in Beijing, which could provide a diplomatic opening with Pyongyang.

A French peacekeeper was killed and three others wounded Saturday when UN forces in southern Lebanon came under small-arms fire near the village of Ghandouriyeh, according to French President Emmanuel Macron and the UNIFIL peacekeeping mission. The attack occurred during a patrol clearing explosive ordnance to re-establish links with isolated UNIFIL positions. Two of the wounded peacekeepers are in serious condition.

Both Macron and UNIFIL blamed Hezbollah for the attack, though the militant group denied involvement and called for caution in assigning blame until Lebanon's Military Tribunal completes its investigation. The dead soldier was identified as Staff Sgt. Florian Montorio of the 17th Parachute Engineer Regiment. France's Armed Forces Minister Catherine Vautrin said Montorio was killed during an ambush while on a mission to open a route to a UNIFIL post that had been isolated for several days.

The incident came just one day after a 10-day ceasefire took effect between Israel and Hezbollah, though it remains unclear to what extent Hezbollah would abide by a truce it did not help negotiate. Macron spoke with Lebanese President Joseph Aoun and Prime Minister Nawaf Salam, calling on Lebanese authorities to identify and prosecute those responsible and ensure the safety of UNIFIL soldiers. The attack occurred during a broader conflict that began March 2 when Hezbollah launched rockets into Israel following U.S.-Israeli attacks on Iran, leaving nearly 2,300 people dead in Lebanon.

President Trump signed legislation Saturday extending Section 702 of the Foreign Intelligence Surveillance Act until April 30, a short-term renewal that followed the collapse of two longer-term proposals in Congress. The bill was approved by the Senate on Friday in a last-minute scramble to prevent the controversial surveillance authority from expiring Monday.

Section 702 permits the CIA, National Security Agency, FBI, and other agencies to collect and analyze vast amounts of overseas communications without a warrant, which can incidentally sweep up communications involving Americans who interact with foreign targets. Trump and Republican leaders have pushed for renewal as a matter of national security, while critics express concerns about civil liberties and want requirements for warrants before authorities access Americans' communications.

The stopgap measure came after both a clean 18-month renewal backed by Trump and GOP leaders and a House Republican five-year extension with revisions collapsed in Congress. The short extension sets up another showdown when the authority expires at the end of April. Trump signed the bill without immediate comment Saturday.