US Secretary of State John Kerry leaves his hotel on the way to a meeting with Iranian Foreign Minister Mohammad Javad Zarif in Vienna, Austria July 5, 2015. [Photo/Agencies]

VIENNA - Iran and world powers aimed to finish the latest round of nuclear talks "in the timeframe" that all parties have set out, said US Secretary of State John Kerry in Vienna on Sunday.

"That's our goal," Kerry said on Sunday, two days ahead of the July 7 deadline,while adding that the U.S. will "put every bit of pressure possible on it to try to do so".

After meeting with his Iranian counterpart Mohammad Javad Zarif on Sunday afternoon, Kerry told reporters that "it is now time to see whether or not we are able to close an agreement", with his foreign minister colleagues returning back to Vienna on Sunday.

However, despite genuine progress made in the past few days, Kerry said: "We are not yet where we need to be on several of the most difficult issues."

Kerry also told reporters that while he completely agrees with Zarif that Iran and world powers "have never been closer" to a deal, the negotiation could go either way at this point.

"We want a good agreement. Only a good agreement. We are not gonna shave anywhere at the margins just to get an agreement," Kerry said, adding that "we're not there yet, I emphasize that."

Meanwhile, European Union foreign policy chief Federica Mogherini also said on Thursday: "We're moving forward, but we're not there yet."

Zarif said on Friday in a video on YouTube that despite some remaining differences, Iran and its counterparts "have never been closer to a lasting outcome".