Trump on Friday evening reasserted his openness to reaching a new Iran deal "that forever blocks its path to a nuclear weapon, addresses the entire range of its malign actions, and is worthy of the Iranian people".
The 2015 Iranian nuclear deal rolled back sanctions against Tehran in exchange for a reduction in the country's nuclear abilities.
On Monday, the administration said it restored previously lifted sanctions on Iranian banking, shipping and energy.
In response, Iranian President Hassan Rohani said in speech broadcast on state TV on November 5 that Iran will break US sanctions and continue to sell oil. USA light crude was 15 cents lower at $62.99.
The sanctions also cover 50 Iranian banks and subsidiaries, more than 200 persons and vessels in its shipping sector, Tehran's national airline, Iran Air, and more than 65 of its aircraft, a U.S. Treasury statement said.
News of waivers on the sanctions weighed on prices, analysts said.
Iranian Foreign Minister Javad Zarif, however, told USA Today his government is open to talks with the US if the Trump administration changes its approach to the nuclear deal.More news: West Indies opt to bat in 5th ODI
Japanese buyers of Iranian crude oil are expected to prepare to resume imports from the Middle Eastern nation after Tokyo was granted a waiver from US sanctions that kicked in this week, trade minister Hiroshige Seko said on Tuesday.
Iranian oil accounted for about 5 percent of Japan's crude oil imports before purchases were cut.
Tehran vowed to defy the economic war while Iranian clerical rulers have dismissed concerns about the impact on the economy.
He said the USA policy is to levy "maximum economic pressure" on the country.
"China opposes unilateral sanctions and long-arm jurisdiction", AFP quoted foreign ministry spokeswoman Hua Chunying as saying at a regular briefing with reporters on Monday. The other parties to the deal - Britain, France, Germany, China and Russian Federation - say they will not leave.
But the official said that because a stronger oil supply is anticipated for next year, "that will allow us to accelerate the path to zero" imports from Iran.
He called on Iran's leaders to immediately give up support for terrorism, stop proliferating ballistic missiles, end destructive regional meddling and abandon their nuclear ambitions in order to escape the crushing sanctions.
"The eight countries which have been exempted have already reduced imports on our request and out of these two have completely stopped importing oil and will not start imports till the sanctions remain in place".