Though party lines divide many Americans' opinions on the ongoing US-Iran war, strong opposition to Donald Trump's four-month-long operation has been declining. 

The latest Daily Mail/JL Partners poll of 1,059 registered voters found that the number of Americans who believe starting the war was wrong is declining, while the number who think it was right is climbing. 

In May, 52 percent of voters polled believed launching military action against Iran was wrong; the latest poll found that has come down six points and is now 47 percent of voters. 

Meanwhile, 35 percent of voters now say the military operation was the right choice, up from 33 percent a month ago. 

Split by party, 64 percent of Republicans claim the war was the right decision while 66 percent of Democrats say the opposite.   

The number of voters who strongly oppose the war in hindsight dropped eight points, from 35 percent to 27 percent, the survey taken from June 24 to June 26 found. 

The results show that Americans are viewing the war more favorably after the President signed a memorandum of understanding with Iran last week to halt attacks while the two negotiate a larger peace deal. 

However, after Iran attacked cargo ships in the Strait of Hormuz on Thursday, and Trump ordered a retaliatory salvo on Friday, it is unclear whether the agreement will hold. 

And even if a deal is reached, many Americans are skeptical about whether or not it will stay in place. 

Just 33 percent of those surveyed said it is likely that a peace deal will hold in the long term if one is struck. On the other hand, 49 percent said it is unlikely to hold. 

Trump's current MOU with Iran has overwhelming support, with a 25-point edge over those who oppose it. 

'Americans clearly want this war to end and are welcoming the deal - even if they are skeptical when they hear more about it,' JL Partners co-founder James Johnson said.

'But if it doesn’t hold, it’s not going to mean much. With more US strikes in the Strait of Hormuz, that casts even further doubt for the American public. The bottom line is these numbers won’t hold if the peace doesn’t.'

Overall, voters say they are opposing the war less and supporting it more, if reluctantly. 

The President's MOU signed last week to kick off a 60-day ceasefire period to negotiate specifics regarding denuclearization and economic reintegration has been met with support. 

Still, there are doubts voters have about whether any long-term deal will last. 

Given that the ceasefire was breached by the Islamic Republic and the US has since struck Iranian targets in return, there is real reason to believe that future talks could be on ice.

Trump said last week that he would 'go back to shooting at them, dropping bombs on ⁠their head' if Iran broke the ceasefire.

On a different front, Israel and Lebanon struck an agreement mediated by Secretary of State Marco Rubio on Friday. 

Ambassadors to the US from both nations signed a framework described as a 'first step' to peace. 

Though few details of the deal were shared, the document does not include Hezbollah, the Iranian-backed militants in Lebanon that have been warring with Israel. 

Israeli Prime Minister Benjamin Netanyahu said that the framework allows Lebanese forces to retake control of territory seized by Israel.