An Iranian woman walks past an anti-U.S. mural on the wall of the former U.S. embassy in Tehran October 12, 2011. (REUTERS)

TEHRAN, July 8 (Xinhua) -- Iranian Petroleum Ministry announced Sunday that there has been no major change in Iran's production and export of crude oil despite U.S. sanction threats.

Iran has plans to counter U.S. President Donald Trump's threats to stop Iran's oil sales, and "the plans are working successfully," Press TV quoted Iran's Petroleum Minister Bijan Namdar Zanganeh as saying on Sunday.

The Iranian minister also criticized Trump's pressure on Saudi Arabia to increase its supplies and said such efforts would destabilize oil market.

The governing principles in Organization of the Petroleum Exporting Countries (OPEC) would never allow such political pressures to change the directions of the market, he said.

Besides, the anti-Iran efforts by the U.S. president are largely to blame for the high oil prices in international markets, he added.

On Saturday, Zanganeh accused Trump of "interfering" in OPEC affairs, saying that Trump's order to oil producing countries to raise output "is very insulting to the people of these countries and would undermine their national sovereignty and destabilize the oil market."

Iran's petroleum minister said that "political issues should not interfere in the crude market, and supply and demand should determine the final oil price."

"But some political measures and instabilities spark concerns in the oil market and increase its price, including Trump's insulting order to some OPEC members," Zanganeh said.

Last Saturday, Trump said Saudi Arabia had pledged to increase its oil output by 2 million barrels per day "to compensate for falling output in Venezuela and Iran."

On Wednesday, Trump said OPEC is "driving oil prices higher," urging the cartel to reduce the price at the soonest.

Hossein Kazempour Ardebili, Iran's ambassador to the OPEC, said the strong rhetoric by Trump against OPEC and oil producers could soon push up crude prices to as high as 100 U.S. dollars per barrel.

On June 26, the U.S. Department of State said that it has been pushing countries to stop importing oil from Iran by November. It said that the United States was "not granting waivers" to any country which was in business with Iran.

Following Trump's decision to quit the historic Iran nuclear pact on May 8, the United States vowed to re-impose sanctions lifted under the accord against Tehran and inflict punishments like secondary sanctions on nations that have business links with Tehran.

Firms that were doing business in Iran were given up to 180 days to wind up investments, otherwise, they risk huge fines, it said.

Washington's withdrawal from the landmark Iran nuclear deal was widely criticized across the world. And some of its major European allies have been working to prevent the 2015 deal from falling apart.

Oil prices rebounded strongly following the message from the U.S. Department of State.

On Saturday, a petroleum ministry official told state-run IRNA news agency that the U.S. sanctions against Iran's oil exports will weaken the OPEC.

"Iran's oil will not lose its customers because a lot of companies are buying oil from the country," said Moayyed Hosseini Sadr, the ministry advisor.

"There might be a slight decline in Iran's oil sale, but different companies' secret purchase of Iran's oil can compensate it," he said.

However, if the United States keeps pressures to ban Iran's crude sales, "it would disrupt OPEC plans because Iran produces five percent of the world total oil output and this is a significant amount," he added.

"There will remain no such organization (as OPEC) in the future after continuation of the sanctions" against Iran, he was quoted as saying.

South Korean embassy in Tehran on Saturday denied that the country has stopped oil imports from Iran, IRAN Daily reported.

"The embassy of the Republic of Korea denies any claims that it would not lift any Iranian crude and condensate in July," the South Korean embassy responded to the report.

"The Korean government is negotiating with the United States to get exemptions from the restrictions on Iranian oil purchases," it said.

South Korea has bought nearly 296,000 barrels of oil from Iran in the first five months of the Iranian calendar year (starting on March 21), and is the biggest buyer of Iranian oil after China and India.