This would make for a great poll, but will hold off for now.
From Forbes, March 15, 2016:
Russian Energy Minister Alexander Novak traveled to Tehran on March 14 on a trade mission where he met with Iranian Petroleum Minister Bijan Zanganeh and Iranian Energy Minister Hamid Chitchian. On the agenda were discussions about the proposed “production freeze”, which Iran has consistently and unequivocally stated it will not consider joining until after its oil production reaches the pre-sanctions level of 4 million barrels per day.
Neither Russia nor Saudi Arabia had planned significant production increases in 2016.
Russia’s January production of 10.88 million barrels per day was already at a post-Soviet record high. Russia could freeze production but still increase exports of crude oil relative to oil products by manipulating its tax regime.
Saudi Arabia’s output was relatively stable in January at near record levels of 10.23 million barrels per day.
Iraq has signaled that it will consider participating in the proposal, but only if all other major OPEC and no-OPEC producers were in agreement. By declaring that its January production was 4.775 million barrels per day, Iraq has put forth an inflated production ceiling that doesn’t reflect actual production but would lock-in a targeted production increase. Iraq’s January oil production was closer to 4.35 million barrels per day.
Getting Iran on board will require finding a mutually acceptable production ceiling. Yet, Iran has refused to cap its production at January levels, which OPEC secondary sources estimate to be 2.93 million barrels per day. In Tehran’s perspective, this would leave an unacceptable amount of money on the table considering that pre-sanctions production was around 3.8 million barrels per day. Iran produced an estimated 3.22 million barrels per day in February.