Oil prices fell on November 5 as the start of USA sanctions against Iran's fuel exports was softened by waivers that will allow major buyers to still import Iranian crude, while Tehran said it would ignore Washington and continue to sell.
President Donald Trump's administration re-imposed sanctions lifted under the 2015 nuclear deal after pulling out of the global agreement reached between Iran, the United States and five other powers: Britain, France, Germany, China and Russian Federation.
The US Secretary of State, Mike Pompeo, said: "I promise you that doing business in Iran in defiance of our sanctions will ultimately be a much more painful business decision than pulling out of Iran".
Seoul also won an exemption from the USA to continue financial transactions with the sanctioned Iranian central bank to facilitate oil imports, the official said.
He said that two of the eight jurisdictions will wind down Iranian oil imports to zero in "weeks" and the six others will import "at greatly reduced levels".
Many of these companies initially were targeted by sanctions under President Barack Obama, but the restrictions were subsequently lifted when the USA struck a deal with Iran in 2015 over its nuclear ambitions. "Iranian exports show a decline of more than 1 million barrels per day (bpd) as of October from May", said Edward Bell of Emirates NBD bank.
The U.S. retains the flexibility to tighten sanctions further in coming months, but Monday's measures will deprive the rulers in Tehran of more cash for their foreign adventures.
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Under the EU's proposal, Northern Ireland would remain in the customs union and in the single market for goods. The Department for Exiting the European Union (DEXEU) said: "We wouldn't comment on private meetings".
"This is an economic war against Iran but".
The first round of the anti-Iran bans - which had been lifted under the accord - were re-imposed in August.
The second wave of renewed USA sanctions on OPEC's third largest exporter officially started on Monday targeting Iran's energy, shipbuilding, shipping, and financial sectors.
The president gave companies a specified period to wind down business with Iran - they face punishment from the USA government for failing to do so.
Benchmark Brent crude futures were down 20c at $72.97 a barrel by 9.29am GMT.
Trump said in a statement Friday that the goal is to force Iran's leaders to choose either to abandon what he calls Iran's "destructive behavior" or to "continue down the path toward economic disaster".
Trump announced in may that Washington is out of agreement with Iran on its nuclear program.
The secretary of state also said three ongoing non-proliferation projects in Iran are exempt from sanctions.