​A dispute between Iran and South Korea escalated Sunday over an escalating oil bill dispute between the US and the Asian country that the Iranian government has threatened to blacklist.

Last week, South Korea received a notice from the US government notifying it of sanctions and warnings to stop purchasing Iranian oil, worth over $3 billion in total. South Korea soon scrambled to banish the letter before continuing with its purchase.

“Instead of canceling the letter, we provided it to the Americans,” a diplomatic source told Reuters.

Following the March 1 letter from the US to South Korea regarding the Iranian gas deal, Iranian Foreign Minister Mohammad Javad Zarif wrote to Korean Foreign Minister Kang Kyung-wha, calling for sanctions to be “reinstated on the Koreans.”

South Korea said it would freeze its oil purchases until the dispute was resolved.

Instead of canceling the letter, we provided it to the Americans

This has angered the Iranian government, who see it as a violation of international sanctions against the Islamic Republic.

“Such behavior is also in violation of international conventions,” said Zarif, on Twitter .

This trend of aggressive tactics and unpredictability from the US on a range of issues was a recurring theme at the United Nations Security Council meeting on Saturday.

The US presidency has focused on flexing its muscle in world affairs in response to what it has described as the Iranian threat.

Zarif was not the only one to express his concerns about Donald Trump’s administration in the run-up to Sunday’s tête-à-tête meeting in New York with Kang, the Korean foreign minister.

In an interview with CNN Friday evening, Russian Foreign Minister Sergey Lavrov told Wolf Blitzer he was “very concerned” that the US and Europe have not come to a “mutually acceptable deal” with Iran.

​”You can’t do that by symbolic spasms of intolerance and provocations,” said Lavrov of the backlash against the “provocations” of the Trump administration.

“We believe that those spasms must be put to an end – by respectful diplomacy,” he said.

The row comes on the heels of Trump’s decision to withdraw the US from the 2015 Iran nuclear deal.

The US president announced in May last year that it would revoke the agreement with Iran, which was signed by the US, the UK, France, China, Russia and Germany.

​The agreement was struck over concerns that the Iranian nuclear program was headed toward becoming an advanced weapons program, but it proved to be quite beneficial for Iran, according to a May 2018 report from the Atlantic Council.

“The US withdrawal from the Joint Comprehensive Plan of Action (JCPOA) had little impact on Iran’s nuclear program, which continues unabated,” writes Michelle Conlin for The Atlantic Council’s Institute for Science and International Security (ISIS).

The ISIS study notes that though there are new nuclear and missile measures in place, Iran is continuing to produce and install centrifuges for 20 percent enriched uranium that it had not done before the JCPOA and it is continuing to stockpile enriched uranium up to 20 percent.

​*This story was amended to clarify the source of the quote.