President Donald Trump suggested that Iran hasn't yet violated the ceasefire.
President Donald Trump announced "major combat operations" against Iran on Feb. 28, with massive joint U.S.-Israeli strikes targeting military, government and infrastructure sites.
Following the announcement of a two-week ceasefire, initial U.S.-Iran talks in Pakistan in April failed to reach a peace deal.
Trump later announced the open-ended extension of the ceasefire and the continuation of a U.S. blockade until negotiations are concluded "one way or the other."
The Israel Defense Forces said in a Thursday statement that its Wednesday airstrike in southern Beirut -- the first on the capital since a ceasefire was agreed between Israel and Hezbollah last month -- killed Ahmed Ali Balout, the commander of Hezbollah's elite Radwan Force commando unit.
Balout, the IDF said, was "eliminated in a precise strike, in the Dahiyeh area of Beirut."
The U.S. and Iran are negotiating over a memorandum of understanding (MoU) aimed at breaking through the standoff in the Strait of Hormuz and setting a timeline for both sides to work out a more comprehensive nuclear deal.
The one-page MoU currently on the table from the Trump administration would see Iran easing its grip on the Strait of Hormuz and the U.S. gradually lifting its naval blockade of the country's ports over a 30-day period, according to officials familiar with the matter.
Officials underscore that nothing has been formally agreed to at this point and that some issues -- including ones related to Iran's ongoing demands to charge a toll for transiting the strategic waterway -- still need to be resolved.
Iranian and US negotiators have passed multiple draft versions of the MoU back and forth in recent days, and the administration is currently waiting for feedback from Iran on several points, they say.
In its current form, the one-page MoU does contain terms related to Iran's nuclear program, but the expectation is that most of the specifics would be negotiated over the 30-day period.
Officials have so far declined to describe the proposed MoU as a take-it-or-leave-it offer.
Israel launched strikes on Beirut Wednesday, targeting a Hezbollah commander, according to a joint release from Prime Minister Benjamin Netanyahu and Defense Minister Yisrael Katz.
"The terrorists, led by Radwan, were responsible for firing at Israeli settlements and harming IDF soldiers. No terrorist has immunity - Israel's long arm will catch every enemy and murderer," Netanyahu and Katz said.
U.S. Central Command said that U.S. forces fired on and disabled an Iranian-flagged tanker around 9 a.m. ET Wednesday in the Gulf of Oman.
In a press release, CENTCOM said the empty tanker was attempting to sail to an Iranian port after "repeated warnings."
"U.S. Central Command (CENTCOM) forces observed M/T Hasna as it transited international waters enroute to an Iranian port on the Gulf of Oman. American forces issued multiple warnings and informed the Iranian-flagged vessel it was in violation of the U.S. blockade," CENTCOM wrote in a press release Wednesday.
Officials said after the Hansa's crew failed to comply, forces fired "several rounds from the 20mm cannon gun of a U.S. Navy F/A-18 Super Hornet launched from USS Abraham Lincoln (CVN 72)."
The shots hit the tanker's rudder, disabling its movement. "Hasna is no longer transiting to Iran," CENTCOM wrote in the release.
This is not the first time U.S. forces have fired on tankers attempting to bypass the blockade.
"The U.S. blockade against ships attempting to enter or depart Iranian ports remains in full effect. CENTCOM forces continue to act deliberately and professionally to ensure compliance," CENTCOM said.
-ABC News' Nathan Lee
