AMNA NAWAZ: Welcome to the "News Hour."

As the U.S.

and the world wait to hear if there will be diplomatic progress between the U.S.

and Iran, U.S.

fighter jets today fired on Iranian vessels in the Strait of Hormuz as part of the ongoing U.S.

blockade.

Meanwhile, Secretary of State Marco Rubio continued his visit to Rome, urging Europe to do more to reopen the strait.

Nick Schifrin reports on the day's developments.

NICK SCHIFRIN: In the Strait of Hormuz today, the moment an American fighter jet disables an Iranian tanker by striking its smokestack.

F-18s struck two empty Iranian tankers today, accusing them of trying to run the U.S.

blockade to reach Iranian ports.

In the strait, the U.S.

and Iran are in a tug-of-war, and it's pulling at the cease-fire seams.

Last night, Iran fired missiles at U.S.

warships transiting the strait, as shown in this Iranian military video.

In response, the U.S.

says it struck Iranian small boats like these and targeted launch sites and Iranian military assets in at least three locations onshore.

DONALD TRUMP, President of the United States: They trifled with us today.

We blew them away.

They trifled.

They call that a trifle.

NICK SCHIFRIN: Last night, after a driving tour of a drained Lincoln Memorial reflecting pool, the president once again threatened Iran if it didn't make a deal.

DONALD TRUMP: If there's no cease-fire, you're not going to have to know.

You're just going to have to look at one big glow coming out of Iran, and they'd better sign their agreement fast.

NICK SCHIFRIN: But, today, Iranian Foreign Minister Abbas Araghchi said threats like those make a deal less likely.

He wrote: "Every time a diplomatic solution is on the table, the U.S.

opts for a reckless military adventure.

Iranians never bow to pressure, and diplomacy is always the victim."

The ongoing diplomacy is over a memorandum of understanding that would open the Strait of Hormuz, cap Iran's nuclear program, and lift U.S.

sanctions on Iran and unfreeze Iranian assets.

MARCO RUBIO, U.S.

Secretary of State: We're expecting a response from them today at some point.

Their system is still highly fractured and a bit dysfunctional as well.

So that may be serving as an impediment.

I hope it's a serious offer.

NICK SCHIFRIN: Secretary of State Marco Rubio traveled to Rome to talk Iran and the transatlantic rift sparked by initial European refusals to allow bases to be used for American attacks on Iran.

MARCO RUBIO: One of the main reasons why the U.S.

is in NATO is the ability to have forces deployed in Europe that we could project to other contingencies.

And now that's no longer the case, at least when it comes to some NATO members.

That's a problem, and it has to be examined.

NICK SCHIFRIN: That examination peaked last week, when President Trump announced he would withdraw at least 5,000 troops from Germany within the next year in response to this comment by Chancellor Friedrich Merz: FRIEDRICH MERZ, German Chancellor (through translator): An entire nation is being humiliated by the Iranian leadership, especially by these so-called Revolutionary Guards.

NICK SCHIFRIN: Today, Rubio played nice for the cameras and released positive statements about his meetings.

And Italian Foreign Minister Antonio Tajani appealed to a historic partnership.

ANTONIO TAJANI, Italian Foreign Minister (through translator): I'm convinced that Europe needs America.

Italy needs America.

But also the United States needs Europe and Italy.

NICK SCHIFRIN: Europeans are developing a plan to help keep the Strait of Hormuz open, but only after the war ends.

And, today, some 1,600 ships in the strait are still stuck, waiting for any progress toward a deal.

For the "PBS News Hour," I'm Nick Schifrin.