Saudi Arabia said it would help fill the gap if Mr Trump imposed sanctions on Iran.Analysts say Saudi Arabia and Russia will act together and the world may need to adapt to higher oil prices.
The market is worried about the worsening situation in the Middle East, which has pushed brent crude above $77.But that would be a good thing for Saudi Arabia, especially considering that Saudi aramco is planning a listing.
Again Capital oil analyst John Kilduff said Saudi Arabia would let crude oil go to 80.
It is now a matter of concern whether Saudi Arabia and Russia will make adjustments at next month's meeting to make up for Iran's supply.
Edward Morse, head of global commodities research at Citigroup, said oil prices could eventually fall if Saudi Arabia and Russia relax production cuts.
Some analysts predict that Iranian exports could fall by between 300,000 and 500,000 barrels a day, a figure of between 100 and 1.5 million barrels in the Obama period.
Iran had objected to extending the deal, so in June OPEC would no longer delay production until the end of the year.
OPEC secretary general Mohammad Barkindo says the market rebalancing is a long process.If OPEC continues to cut production, there may be discord within.The saudis will benefit from the loss of Iran, which is well known to be very antagonistic in the region.