Iranian President Hassan Rohani has said the United States is "more and more isolated" on the matter of sanctions against his country.
Speaking during a televised government meeting on July 14, Rohani said Iran had chosen the path of "perseverance, resistance."
In May, U.S. President Donald Trump withdrew his country from a landmark 2015 deal between Iran and leading world powers that granted relief from some sanctions in exchange for curbs to Iran's nuclear program.
Some of the reimposed sanctions take effect after a 90-day “wind-down” period ending on August 6, while the rest, especially those affecting the oil sector, after a 180-day “wind-down period” ending on November 4.
Both deadlines are meant to provide companies and other entities with a grace period during which to conclude trade and other business activities with or in Iran, the U.S. Treasury Department said in May.
The U.S. decision has hit the Iranian economy hard, with many international firms leaving the country since Trump announced the U.S. withdrawal from the accord on May 8. Iran's currency, the rial, has lost about half its value against the U.S. dollar over the last nine months.
"The illegal logic of the United States is not supported by any international organizations," Rohani said.
Despite U.S. sanctions, Rohani said Iran continued to develop economic relations around the world.
"We are very hopeful that the trend of economic engagement with the world will continue as before," he said.
Rohani's statements came a day after Ali Akbar Velayati, a top adviser to Iranian Supreme Leader Ayatollah Ali Khamenei and a veteran member of Iran's political establishment, rejected Trump's suggestion that Iran seek a deal with the United States to ease the economic "pain" of the looming sanctions.
Trump said at a news conference in Brussels on July 12: "I know they're having a lot of problems and their economy is collapsing. But I will tell you this, at a certain point, they're going to call me and they're going to say, 'Let's make a deal,' and we'll make a deal. They're feeling a lot of pain right now."
Some Iranian opposition figures and prominent expatriates have also called on Tehran to negotiate directly with Washington to resolve longstanding hostilities between the two nations. But Velayati, while visiting Moscow on July 13, rejected those suggestions.
"We do not want to negotiate with the Americans," he was quoted as saying by Russian news agencies. "These are the people that break agreements with Iran, approved by the UN Security Council. Why would we trust them and hold negotiations with them?"
Velayati said Tehran will simply cope with the sanctions like it has in the past. He suggested Iran will use avenues it has utilized in the past to evade the sanctions to receive payments for its oil exports.
The United States has brought several high-profile cases in recent years against banks and traders who helped Iran launder oil revenues through the global banking system to get around a U.S. ban against using the dollar.
"It will be hard, but we have learned how to do it," Velayati was quoted as saying by Russian news media.