Washington�:�The US and European Union lifted international economic sanctions against Iran implementing a historic deal with Tehran after the UN nuclear watchdog agency confirmed it has begun dismantling its nuclear programme as promised.
The implementation of the deal would also release about $100 billion of Iran's assets and make it easier for India and other countries to do business with Tehran.
India, which had substantially reduced its oil imports from Iran under US pressure, can now freely import oil from Tehran, but would now have to pay for it in dollars.
Due to the sanctions, India has been paying Iran in Indian rupees, with the money kept in an Indian account. India has to now release an estimated $6 billion in pending oil payments to Iran.
President Barack Obama signed an executive order lifting some of the US economic sanctions on Iran, the White House announced.
Secretary of State John Kerry issued a statement confirming the International Atomic Energy Agency has verified that Iran "has fully implemented its required commitments".
"Iran has undertaken significant steps that many, and I do mean many, people doubted would ever come to pass.
"And that should be recognized, even though the full measure of this achievement can only be realized by assuring continued full compliance in the coming years," Kerry said.
With the implementation of deal reached last July, the US, "our friends and allies in the Middle East, and the entire world are safer because the threat of the nuclear weapon has been reduced", he said.
In exchange for lifting sanctions, Iran must reduce its level of uranium enrichment, dramatically reduce the size of its stockpile of enriched uranium, reduce the number of centrifuges, and agree to unfettered international inspections.
The implementation came hours after Iran freed four American prisoners, including Washington Post journalist Jason Rezaian, in exchange for seven Iranian prisoners. Another American, who was not a part of the exchange, also was released.
But several Republican presidential candidates criticized the prisoner swap with frontrunner Donald Trump saying that Iran was getting more in the deal than the US.
"They're getting seven people, so essentially they get $150 billion plus seven, and we get four," Trump said in New Hampshire.
Senator Marco Rubio accused the Obama administration of not pushing hard enough for the American prisoners' release when the US negotiated a deal with Iran last year.
New Jersey Governor Chris Christie said the US should not have had to make any concessions to get the Americans released.(IANS)