The White House said the action is meant to bring Iran's oil exports to "zero" and remove a main source of revenue for the regime.
The officials said market disruption should be minimal for two reasons: supply is now greater than demand and Pompeo is also set to announce offsets through commitments from other suppliers such as Saudi Arabia and the United Arab Emirates.
Brent crude futures rose as much as 3.3 per cent to $74.31 a barrel, the highest since Nov 1, before easing back to $73.82 by 0452 GMT, up 2.6 per cent from their last close.
India, Iran's biggest oil client after China, has nearly halved its Iran oil purchase since November.
Washington had granted the waivers to China, India, Japan, South Korea, Taiwan, Turkey, Italy and Greece - allowing them limited purchases for six months.
On April 17, Frank Fannon, U.S. Assistant Secretary of State for Energy Resources, repeated the administration's position that "our goal is to get to zero Iranian exports as quickly as possible".
"There are no (oil) waivers that extend beyond that period, full stop", he added.
China, which relies on imports for about half of its oil, could present the toughest diplomatic challenge in trying to enforce the Trump administration's ambition of driving down Iran's oil exports.
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South Korea, a close USA ally, is a major buyer of Iranian condensate, an ultra-light form of crude oil that its refining industry relies on to produce petrochemicals.
"Any action by the top oil exporter depends on the certainty of scrapping the waivers and its effect on the oil market", the report says.
Iran is India's third-largest oil supplier behind Iraq and Saudi Arabia.
Takayuki Nogami, chief economist at Japan Oil, Gas and Metals National Corporation (JOGMEC) said the end of the sanction waivers "is not a good policy for Trump".
India and four other remain continue to buy.
South Korea, a close United States ally, is a major buyer of Iranian condensate, an ultra-light form of crude oil that its refining industry relies on to produce petrochemicals.
So far in April, Iranian exports were averaging below 1 million barrels per day (bpd), according to Refinitiv Eikon data and two other companies that track exports and declined to be identified.
China opposes Washington's "unilateral sanctions and long-arm jurisdiction", said foreign ministry spokesman, Geng Shuang.