Iranian Foreign Minister Mohammad Javad Zarif waves from a balcony of the Palais Coburg Hotel where the Iran nuclear talks meetings are being held in Vienna, Monday, July 13, 2015. Joe Klamar/AFP/Getty Images

A deal on Iran's nuclear program will not come to a close in Vienna on Monday, Foreign Minister Mohammad Javad Zarif said. Speaking from the balcony of his hotel, Zarif told reporters that the deal would not be hammered out by the end of the day. This is the third missed deadline since negotiations began in November 2013.

The delay on a deal reportedly stems from a lack of consensus on "political issues" including the language used to describe Iran in a United Nations Security Council resolution, a European negotiator told BBC. The U.N resolution in question had imposed an arms embargo on Iran for the past nine years in order to curb Tehran's involvement in regional conflicts including Syria, Iraq and Yemen.

"None of the negotiating teams want to extend this again," Jim Walsh, an international security expert at MITWalsh, told International Business Times. "I don't think we're going to get another two week extension but it ain't over it until it's over, and it's difficult."

Experts believe that the bulk of the deal's terms have been already settled and all that remains are disagreements about rhetoric."Iran doesn't want them [the negotiators] to refer to Iran's illicit behaviour. I think good diplomats ought to be able to solve that," Walsh said.

Negotiations between Iran and the P5 +1 nations -- U.S. France, Britain, China, Russia and Germany -- are predicted to pass the midnight deadline.

The mood in Vienna remains optimistic, with Jarad Zarif posting on Twitter earlier Monday: "If the Iran deal reached, triumph of diplomacy means we all will have won when we all could have lost."

Iranian President Hassan Rouhani posted a similar statement on his own social media account minutes before Zarif, later deleting the text and republishing it in a new Tweet.

If the Iran Deal is reached, it would be a "victory of diplomacy and mutual respect over outdated paradigm of exclusion and coercion. And this will be good beginning," Rouhani wrote.

Once a deal is confirmed it will be passed to U.S. Congress, which will then have 60 days to review the terms before President Barack Obama can suspend congressional sanctions. BBC reported earlier on Monday that Rouhani had planned to make a speech in Tehran this afternoon, but this has yet to be confirmed.