Trump says US Navy attacked and seized Iranian-flagged cargo ship

The current Iranian negotiations leader, Mohammed Ghalibaf, the speaker of the Iranian Parliament, posted a statement to social media Friday evening stating President Donald Trump "made seven claims in one hour, all seven of which are false."

Ghalibaf's statement also echoes what Foreign Ministry spokesperson Esmael Baqaei said earlier -- that Iran would not allow navigation in the Strait of Hormuz if the American blockade continued, and that navigation will be carried out based on a "designated route" and with "Iranian permission."

He added that the "open or closed status of the Strait and the regulations governing it will be determined by the field, not social media."

The statement went on to say: "Media warfare and public opinion engineering are an important part of the war, and the Iranian nation will not be affected by these tricks."

-ABC News' Victoria Beaule

President Donald Trump said in-person discussions would "probably" happen this weekend. Though two U.S. officials see Monday as the first feasible day that a second round of negotiations could take place in Islamabad. They also note that timing and the delegations are not locked in yet.

Trump has said that Iran has agreed to suspend their nuclear program indefinitely. Though there's still no agreement on how long Iran would suspend uranium enrichment or the terms around that, according to U.S. officials and another source familiar with the state of play. This is the key sticking point.

On Iran's stockpile of highly enriched uranium, a U.S. official says negotiators are discussing multiple ways to address the issue in part because it's possible that not all of it can be downblended within the country, as some might not be stable enough to undergo the process.

The official says there are many details on this front to work out, but that the administration believes the sides are fundamentally in agreement.

At present, Iran's missile program and its support for regional proxies are not being discussed as terms within the potential memorandum of understanding, a U.S. official and another source familiar with the talks said.

-ABC News' Shannon K. Kingston

President Donald Trump continued to tout the progress between the U.S. and Iran upon touching down in Phoenix on Friday, telling reporters that the two countries have had "some very good discussions."

"We've done a good job, but we'll see,” Trump said.

"Talks are going on and will go on over the weekend, and a lot of good things are happening," Trump continued, adding, "That includes Lebanon, too."

Trump acknowledged that there "could" still be differences that the U.S. and Iran need to work out, despite saying earlier Friday that Iran has "agreed to everything."

"Well, there could be," Trump said when asked to respond to reports of Iran claiming the two countries still have significant differences. "Let's see what happens. If there are, we'll have to straighten it out. But I don't think there's too many significant differences."

The president also insisted that the U.S. blockade in the Strait of Hormuz will end once the U.S. and Iran sign a deal.

"When the agreement is signed, the blockade ends," Trump said.

-ABC News' Nicholas Kerr and Emily Chang

The White House is pushing back against claims by the Islamic Revolutionary Guard Corps that vessels transiting the Strait of Hormuz will require permission, reiterating Friday that the Strait is "completely open for business."

"As President Trump said, the Strait of Hormuz is completely open for business, and Iran has agreed to never close the Strait again," White House deputy press secretary Anna Kelly said in a statement when asked to respond to the IRGC's claim. "Thanks to the United States' successful blockade of Iranian ports, the United States also maintains maximum leverage in negotiations to eliminate Iran's nuclear threat for good."

The White House response comes even as ship tracking data shows traffic still shows minimal traffic transiting through the region. About two dozen ships started to make their way toward the strait Friday morning amid announcements from Trump and Iranian Foreign Minister Abbas Araghchi that it was reopened, before most of the ships appeared to turn around and head back into the Persian Gulf, according to ship data from MarineTraffic.

-ABC News' Nicholas Kerr