President Donald Trump has “disgraced” US prestige and would be the ultimate loser from re-imposing sanctions on Tehran.
The United States restored sanctions on the Islamic Republic’s shipping, energy and financial sectors on Friday.
The measures will come into effect on Monday.
“This new US president … has disgraced the remnant of America’s prestige and that of liberal democracy. America’s hard power, that is to say, their economic and military power, is declining, too,” Khamenei said on Twitter on Saturday, quoting a speech he gave earlier in Tehran.
Khamenei was speaking on the eve of the anniversary of the 1979 takeover of the US embassy in Tehran.
“The challenge between the US and Iran has lasted for 40 years so far and the US has made various efforts against us: military, economic and media warfare,” he said.
“There’s a key fact here: in this 40-year challenge, the defeated is the US and the victorious is the Islamic Republic.”
The US said that eight countries would receive a temporary waiver from the sanctions, meaning they will be allowed to keep buying Iranian oil without being penalized.
Turkey said on Saturday that it had received initial indications from Washington that it would be granted a waiver, but is awaiting clarification.
The sanctions are the second set to be re-imposed by the Trump administration since the US withdrew unilaterally from the 2015 nuclear deal in May.
Trump has said he wants to negotiate a new deal with Iran to replace the multilateral agreement, with Tehran making a number of new concessions in return for sanctions relief and the re-establishment of diplomatic ties between Washington and Tehran.
Hossein Askari, professor of international business and international affairs at George Washington University, told Al Jazeera it was extremely unlikely Iran would agree to Trump’s demands.
“The United States has 12 demands, exactly what Saudi Arabia did to Qatar,” said Askari. “One is to say ‘Iran has to end its support for terrorism’. Well, Iran has not supported terrorism for many, many years. That is off the table.
“It says ‘Iran has to end its missile program’. Well, Iran is not going to stop that. Iran faces Israel, with nuclear warheads, the United States is surrounding Iran on all sides and you want Iran to just say, ‘OK, we’re not going to do anything’. That is not going to happen.
“And then, the third thing that’s very important is that they want Iran to stop its operations in Syria. And the Iranian view on that is very simple.
“Syria was the only country that supported Iran during the Iran-Iraq war, when the United States and the Europeans gave outlawed chemical weapons to Iraq to use on the Iranians. It has no choice but to support Syria.”