The third and final day of the latest round of Iranian nuclear talks is set to get underway later on today in Vienna.
So far no agreements have been reached.
However, negotiators at the talks are suggesting both sides clarify their positions.
Michael Mann is a spokesperson for EU foreign policy chief Catherine Ashton, who is the lead negotiator for the P5+1.
"The words that we used to describe the talks yesterday were substantive and useful. I think that still applies so good work is being done, and we continue to work very hard, towards making solid progress".
The head of the Chinese delegation to the talks, Vice Foreign Minister Li Baodong, says progress needs to be made this week.
"The Iran nuclear issue has perplexed the international community for more than ten years, because it is related to the peace and security of the Middle East region and the whole world. We have to move forward. A big step forward is needed."
The talks are designed to create a permanent nuclear deal to replace the interim agreement hammered out in November.
That deal has seen Iran shut down its critical enrichment programs in exchange for temporary sanctions relief for 6-months.
The Iranian side has since gone on-record saying it will not permanently shut down any of its nuclear facilities, noting its long-standing position that its nuclear programs are for peaceful purposes only.
