Negotiations between the US and Iran remain at a standstill as Israel and Hezbollah continue to exchange fire, and Iran demands the release of $24 billion in frozen assets. 

Tehran has made a ceasefire between ‌Israel and Hezbollah a condition for any peace deal with Washington fourth months into the regional war, along with restarting shipping through the Strait of Hormuz.

However, Israel and Hezbollah have continued to trade blows despite agreeing this week to a mediated ceasefire. 

On Friday, Israel killed the head of Hezbollah's engineering unit, Abed Harb, according to the Israel Defense Forces, who also claimed Hezbollah launched surface-to-air missiles at Israeli aircraft. 

The ongoing fighting has stalled peace negotiations. Without a ceasefire in Lebanon, Iran will not move forward with a US deal.

"This war will end only when it ends in Lebanon as well," Iranian Foreign Minister Seyed Abbas Araghchi told Lebanese TV ​station Al Mayadeen late on Thursday.

He warned that Iran would respond if Israel attacks Beirut, saying Tehran had informed all parties that it would not tolerate an assault on the Lebanese capital and that such a move could trigger a return to war.

Iran demands release of its frozen assets

A top Iranian official told CNN on Friday that a potential peace deal between the US and Iran hinges on Washington releasing $24 billion in frozen Iranian assets, warning that renewed military confrontations would send the US "into a dark corridor."

"The negotiations are at a deadlock and (US President Donald) Trump must break this deadlock," Mohsen Rezaei, military adviser to Supreme Leader Ayatollah Mojtaba Khamenei, told CNN. "The ball is in Trump's court," Rezaei said.

In an interview with NBC News, Trump said Iranian leaders have not yet reached a deal because they are "strong" and "proud."

"They're strong, they're proud, there are things they never thought they'd be doing that they're going to have to do. They've got no choice, and it takes a little while," Trump said. 

US-Iran military frictions

Though the US and Iran have extended their April ceasefire, skirmishes continue. 

CNN reported on Friday, citing a ​US ​official, that Iran ​launched multiple ‌drones towards ​the ​Strait of Hormuz, ⁠which ​US ⁠forces shot down.

Iran's Islamic Revolutionary Guard Corps (IRGC) later said it fired on four tankers attempting to cross the Strait of Hormuz without permission.

The US military retaliated for Iran's drone attacks with strikes on Iranian radar sites in what ​it called a defensive ⁠action. 

On Saturday, the IRGC said it targeted US bases in Kuwait and Bahrain with ballistic missiles in response.

(With input from agencies)