"I'm hopeful that everyone in and even outside the organisation will be supportive to whatever requirements we need to do to balance the market", he said.
"I think a million [barrels a day] will be adequate personally", Saudi Oil Minister Khalid Al-Falih said upon arriving to the meeting in Vienna.
Moscow has shown willingness to cooperate with OPEC to cut oil production.
The price of crude has fallen nearly a third since October but Trump has demanded OPEC make oil even cheaper by refraining from output cuts. US senators say, after a briefing with intelligence services, that they are convinced Saudi Arabia's de-facto ruler, Crown Prince Mohammed bin Salman, was involved in Khashoggi's death. However, he noted that all the participants will be listened to in order to arrive at a consensus on the issue. It is the United States where we are seeing the bulk of the increase in oil output.
At a December 2016 meeting, OPEC members had agreed to a production cut to battle a supply glut that saw oil prices drop to $25 per barrel.
Brent oil futures fell as much as 5 percent to below $59 per barrel on fears that there could be no deal but later recovered somewhat, trading down 2 percent by 1325 GMT.
USA oil prices were little changed after the news.
PRICE Futures Group's Phil Flynn on the outlook for oil prices.
Ministers from the core OPEC group, which doesn't include Russian Federation, will meet on Thursday to seek a consensus on exactly who will cut and by how much. The power of OPEC has been diminished, undercutting one of the major geopolitical forces of the last half century.
"Markets.believe the production cut deal will be in range of 1-1.3 million bpd", ANZ bank said on Thursday.
The OPEC countries will now discuss the meeting with Russian Federation, which is not part of OPEC but has been coordinating its output levels to support the market.
Zanganeh said the estimated surplus now on the market amounted to 1.3-2.4 million barrels per day.
During Thursday's meeting, OPEC leaders are expected to discuss how to stabilize crude oil production after USA prices plunged by 22-percent in November - making it the worst month since the financial crisis in 2008. Saudi Arabia is the de facto leader of OPEC so its opinion goes a long way, however, due to the critical nature of this decision, it is likely to wait for Russia's opinion which may come later in the day.
Russia, Saudi Arabia and the United States have been vying for the position of top crude producer in recent years.
OPEC is also riven by internal conflict, especially between regional rivals Saudi Arabia and Iran.
Possibly complicating any Opec decision is the crisis around the killing of journalist Jamal Khashoggi at the Saudi consulate in Istanbul in October.