"I would like to remind that two days ago during the meeting between Saudi Crown Prince Mohammed bin Salman and President Putin a historic decision was made on the cooperation between our countries on prolongation of the OPEC+ [OPEC/non-OPEC] agreement on a termless basis," Novak told reporters.
"We will discuss this issue [in Vienna]. They [parties to the agreement] have also given their preliminary consent to prolongation of the cooperation, the format must be agreed on," Novak said.
The minister added that the prolonged OPEC/non-OPEC agreement would contain no specific oil output volumes.
"It [the deal] is likely to provide [parties to the deal] with an opportunity to decide [on changing the volumes of oil production] if needed," Novak added.
Novak also told journalists that Russia and Saudi Arabia will offer the parties to the oil output cut agreement between the OPEC and a number of non-cartel producers to raise production in the third quarter of 2018 by 1.5 million barrels per day, and then to take further decisions in September.
The decision to soften the deal should give all countries participating in it equal opportunities to increase production proportionally to their reduction quotas, Novak added.
"We need to give the same opportunities to everyone… It's fair to distribute this softening in proportion to the cut-off quotas," he said.