Iranian Foreign Minister Mohammad Javad Zarif has lashed out at the United States for imposing "illegal and draconian" sanctions on Tehran, saying Washington would once again regret its "unwise measures."

"The US administration appears to believe that imposing illegal, draconian sanctions on Iran will bring about such pain to our nation that it will force us to submit to its will no matter how absurd, unlawful or fundamentally flawed its demands are," Zarif said in an online video message on Tuesday.

He added that fresh US sanctions against Iran were an "indiscriminate assault" and said the Islamic Republic has weathered "difficult times" in the face of 40 years of American hostility by relying solely on its own resources.

"Today, we and our partners across the globe will ensure that our people are least affected by this indiscriminate assault in the economic warfare that directly targets the Iranian people," the top Iranian diplomat added.

The administration of US President Donald Trump announced on Monday the re-imposition of the “toughest” sanctions ever against Iran's oil exports, shipping and banking. The bans had been lifted under the 2015 nuclear deal, officially known as the Joint Comprehensive Plan of Action (JCPOA).

The re-imposition of the second set of sanctions came after Trump in May pulled the US out from the agreement reached between Iran and the P5+1 group of countries -- the United States, Britain, France, Germany, China and Russia.

After leaving the deal, the US administration vowed to bring Iranian oil sales to “zero.”

It has, however, agreed to grant waivers to Turkey and seven other countries -- China, India, Italy, Greece, Japan, South Korea and Taiwan -- to continue importing Iranian oil without facing diplomatic consequences.

Elsewhere in his video message, Zarif pointed to gradual change of policies and attitude by previous US administrations towards the Iranian nation and said, "I am confident that Mr. Trump's administration will also reach to a conclusion that such policies will have no impact on determination of the great Iranian nation and the Americans will be obliged to change their policy."

He emphasized that the world stands against the US administration and no country except for some few states in the Middle East and the Israeli regime would abide by Washington.

The foreign minister added that the hostile US measures were aimed at separating the "Iranian people from each other and from the establishment."

He expressed confidence that "bad days" are awaiting the US administration which mostly tries to "cover atrocities of the Saudi regime and the Israeli regime instead of pursuing a policy in line with the US national interests."

Zarif said Washington would be better off rethinking its "longstanding and unconditional support" for Saudi Arabia and Israel, which has "blinded the US to their appalling atrocities."

He added that instead of relying on its "discredited addiction to unilateralism and sanctions…, the US is better off addressing the catastrophes and crises it has engineered in our region."

In an exclusive interview over the weekend with USA TODAY, Iranian Foreign Minister Mohammad Javad Zarif said Tehran would be open to talks with the United States about a new nuclear agreement if Washington changes its "approach" to discussing the 2015 nuclear deal.

He added that Iran would weigh fresh diplomacy if there were "foundations for a fruitful dialogue" on the Iran nuclear reduction deal, stressing, "Mutual trust is not a requirement to start negotiations – mutual respect is a requirement."

In a letter to UN Secretary General Antonio Guterres on Monday, Iran's Ambassador to the United Nations Gholamali Khoshroo said the United Nations must hold the United States to account for its "illegal" move to reinstate sanctions on Tehran.

"The United Nations and its member states, in accordance with the Charter of the United Nations and the international law, should resist against these wrongful acts and hold the United States accountable for such acts," Khoshroo said in his letter.