NEW ORLEANS — The Trump administration is poised to end a program that has allowed five large nations, including China and India, to buy Iranian oil despite American sanctions, two senior American officials said on Sunday, a decision that is intended to squeeze Tehran’s government but could lead to higher oil and gasoline prices.

The move to choke off all exports of Iranian oil is part of an increasingly aggressive pressure campaign by the Trump administration to starve Iran of revenue with the goals of forcing political change among its ruling clerics and getting it to rein in its military actions across the Middle East.

But the decision also risks increasing frictions with other nations, including some major American allies, and hindering other policy priorities, particularly trade talks with China and cooperation from Beijing on containing North Korea.

Since May 2018, when President Trump withdrew from a nuclear deal that the United States and other major world powers reached with Iran in 2015, the Trump administration has relied on economic sanctions as the core tactic of its campaign.