The United States offered to remove all sanctions on Iran in exchange for talks but Tehran has not yet accepted the offer due to the current "toxic atmosphere", Iranian President Hassan Rohani said on Friday.
However, U.S. President Donald Trump has since negated Rohani in a tweet, claiming the Iranians asked him to lift the sanctions in order to meet, and he refused.
Rohani, speaking on his return from the United Nations General Assembly in New York, said he met there with U.S. officials at the insistence of Germany, Britain and France.
"It was up for debate what sanctions will be lifted and they (the United States) had said clearly that we will lift all sanctions," Rohani said, according to his official website.
Iran was ready for negotiations but not in an atmosphere of sanctions and pressure, the Iranian president said.
"This action wasn't in a manner that was acceptable, meaning that in the atmosphere of sanctions and the existence of sanctions and the toxic atmosphere of maximum pressure, even if we want to negotiate with the Americans in the 5+1 framework, no one can predict what the end and result of this negotiation will be," he said.
Crude slipped on the report, adding to earlier losses caused by a faster-than-expected recovery in Saudi output, slowing Chinese economic growth, a Wall Street Journal report saying that Saudi Arabia had agreed a partial ceasefire in Yemen. Brent crude was trading below $62 a barrel.
Rohani did not meet U.S. President Donald Trump in New York and European and Gulf officials expect Washington to keep tightening the vice on Iran's economy.
The United States and Iran are at odds over a host of issues, including the U.S. withdrawal from the 2015 Iran nuclear deal, U.S. accusations - denied by Tehran - that Iran attacked two Saudi oil facilities on Sept. 14, and Iran's detention of U.S. citizens on what the United States regards as spurious grounds.
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