VIENNA (Sputnik) � The ongoing Iran nuclear talks have entered a very sensitive stage, Iranian Foreign Minister Mohammad Javad Zarif said after he landed Tuesday in the Austrian capital of Vienna.

arif was accompanied by�the head of�Atomic Energy Organization of�Iran, Ali Akbar Salehi, and senior presidential adviser Hossein Fereydoun.

"Talks are at�very sensitive stage, Salehi's presence will help a lot, we are certainly making progress," Zarif told Iranian media Tuesday.

Tuesday marks the deadline for�reaching a deal between�Iran and the P5+1 � Russia, China, France, Britain, the United States and Germany � over�Tehran's nuclear program.

Iran's top diplomat noted that Iranians will only accept a fair, balanced deal with�international negotiators. A good deal cannot be achieved without�recognition of�Iran rights, he noted.

"Only a balanced, respectable solution is sustainable otherwise Iran will not accept it," Zarif warned.

The crucial talks that are aimed at�curbing Iran�s nuclear research in�exchange for�sanctions easing are expected to�go several days beyond�the initial deadline.

The comprehensive deal, discussed in�Vienna, builds on�the framework that was agreed on�in the Swiss city of�Lausanne in�April. Tehran is expected to�cut back uranium enrichment and decrease the number of�centrifuges, but�inspection of�its nuclear sites remains a contentious issue.

By Sputnik