Some oil analysts have said they expect Iranian crude exports to fall by as little as 200,000 barrels per day (bpd), while others put the figure closer to 1 million bpd.
USA shale production is expected to hit a record 7.18 million barrels per day (bpd), the Energy Information Administration said.
On the bearish side some traders believe prices won't move almost as high because of rising USA production and the possibility that other suppliers from within OPEC will step up output in order to counter the Iran disruption.
But that's exactly what Iran Oil Minister Bijan Namdar Zanganeh said on state television Thursday.
As soon as oil prices rose after Trump's announcement, Saudi said it was ready to offset any supply shortage, Reuters reported an OPEC source familiar with the kingdom's oil thinking telling it.
Iran produces 4% of global oil supplies.
Oil prices shot up to a one-year high on Thursday as traders prepared for possible renewed USA sanctions against Iran, and the gap between supply and demand in the market narrowed down.
RBI may harden stance as inflation rises in April
However, economists said that the price rise was expected to continue to rise over the remainder of this quarter. Among primary articles, inflation in food articles stood at 0.87% in April, against a decline of 0.29% in March.
US West Texas Intermediate (WTI) crude futures were up $1.51 per barrel, or 2.2 percent, at $70.57 a barrel, near highs also last seen in late 2014. The International Energy Agency has said "with just under half of global oil supply subject to restraint and oil demand growing steadily, the impact on stocks has been substantial".
USA light crude was down 16 cents at $71.20, having touched a 3-1/2 year high of $71.89 on Thursday.
Washington has given European firms doing business in Iran up to six months to wind up investments or risk US sanctions and they are also forbidden from signing any new contracts with Iran.
Lukman Otunuga, Research Analyst at FXTM told AMEinfo that global crude oil prices extended gains on Thursday and oil bulls received further inspiration from heightened geopolitical tensions in the Middle East which fueled concerns of potential supply disruptions.
This is 27% over mid-2016 and means that USA production is getting closer to that of Russian Federation, which is largest oil producer with about 11 million barrels per day.
On Monday, however, markets were held in check by news of a rise in USA drilling for new oil production.
This would make the United States the world's largest producer, ahead of both Russian Federation and Saudi Arabia.