Iran and the US say ‘hard work’ is needed to nail down a comprehensive final deal on Tehran’s nuclear program.

“We need to work really hard in order to be able to make progress and move forward,” Iran’s Foreign Minister Mohammad Javad Zarif told reporters at the start of talks with US Secretary of State John Kerry in Vienna, Austria, on Saturday.

“We’re determined to do everything we can in order to be able to get to this important milestone,” he added.

Kerry, for his part, said he was hopeful but stressed that there was a lot of hard work to do to clinch a final agreement.

“I think it’s fair to say that we are hopeful. We’ve got a lot of hard work to do with some very tough issues. We all look forward to getting down to the final effort here to be able to make a deal possible. I think everybody would like to see an agreement. But we have to work through some difficult issues,” Kerry added.

[caption id="" align="alignnone" width="555"] Iranian Foreign Minister Mohammad Javad Zarif (C) and his deputies in a meeting with the US delegation in Vienna, Austria, June 27, 2015 (IRNA photo)[/caption]

The meeting between Zarif and Kerry lasted for one and a half hour and the two sides are expected to resume the negotiations after a break.

Also present in the talks were European Union Political Director Helga Schmid, US Energy Secretary Ernest Moniz, US Under Secretary Wendy Sherman as well as Iranian Deputy Foreign Ministers Abbas Araqchi and Majid Takht-e-Ravanchi.

Meanwhile, EU foreign policy chief Federica Mogherini, German Foreign Minister Frank-Walter Steinmeier, British Foreign Secretary Philip Hammond and French Foreign Minister Laurent Fabius are also expected to join the talks.

There is no word yet on whether Russian Foreign Minister Sergei Lavrov and his Chinese counterpart Wang Yi will also attend the talks.

Representatives from Iran and the P5+1 group – the US, the UK, France, China and Russia plus Germany – are holding extensive talks to finalize the text of a possible deal over Tehran’s nuclear program by the end of June.

The two sides seek to seal a comprehensive deal based on a mutual understanding on the key parameters agreed upon in the Swiss city of Lausanne on April 2.

By Press TV