Well, President Trump says it will be a great deal for all or no deal at all.

The lead starts right now.

And tonight, sources say the White House is optimistic about a deal to end the war with Iran,

despite disputes today about the country's nuclear program.

So what would an agreement mean for the Strait of Hormuz and those sky-high gas

prices? And we've reached the final hours of a nasty fight between Texas Republicans as John

Cornyn and Ken Paxton battle for the party Senate nomination. Will Trump's last-minute endorsement

have a big impact? We're live in the Lone Star State just ahead.

And on this Memorial Day, we'll be joined by two U.S. Marine Corps veterans

who survived an IED blast in Iraq,

and will help us remember the reason for this Memorial Day

by honoring the heroes who didn't make it home,

like my dear friend Chase Conley.

And welcome to the lead. I'm Pamela Brown and for Jake Tapper on this Memorial Day. And we start in our world lead. We are tracking the very latest on negotiations to end the war between

the United States and Iran. So the deal remains in limbo right now, and U.S. officials say that's because of disputes over

language about Iran's nuclear program and the lifting of sanctions.

There is optimism, though, that this could be resolved soon.

And oil prices reflected that optimism dropping sharply today following talk of a potential peace deal.

Still, the U.S. has been looking for firm commitments from Iran that it will get rid of its

stockpile of highly enriched uranium and not pursue a nuclear weapon.

On Sunday, a U.S. officials said Iran had agreed in principle to those points, but Iran says it is

not discussing details of its nuclear

...