DUBAI (Reuters) - Iranian President Hassan Rouhani said on Monday new U.S. sanctions blacklisting Iran’s central bank for a second time pointed to U.S. “desperation” in the face of Iranian resistance.

President Donald Trump last year quit a 2015 nuclear pact between Iran and six world powers, reimposing and then tightening sanctions that had been lifted under the deal in return for Iran curbing its nuclear program.

The United States on Friday imposed further sanctions, including on Iran’s central bank which was already blacklisted, following Sept. 14 attacks on Saudi oil facilities that Riyadh and Washington have blamed on Iran.

“Americans are sanctioning institutions that have already been blacklisted. This signals America’s complete desperation and shows that it’s “maximum pressure” has failed ... as the great Iranian nation has resisted successfully,” Rouhani said in remarks carried by state television.

Tehran has flatly denied any involvement in the attacks which was claimed by Yemen’s Houthi movement, an Iran-aligned group fighting a Saudi-led alliance in Yemen’s civil war.

Prime Minister Boris Johnson said on Monday Britain believes it is very likely Iran was behind the Sept 14 attacks. He said London will work with the United States and European allies to reduce tensions in the Gulf.

“If Iran was behind this attacks, nothing would be left of this refinery,” Iranian Foreign Minister Mohammad Javad Zarif told reporters in New York.

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U.S. Secretary of State Mike Pompeo said on Sunday the United States aimed to avoid war with Iran and the additional troops ordered to be deployed in the Gulf region were for “deterrence and defense”.

“As a diplomat both secretary Pompeo and I should try to avoid war, not to wage war,” said Zarif.

Iran has threatened a crushing response to any military strike following the Sept 14 attacks, though it said the Islamic Republic had no desire for conflict in the Gulf region.

“The region has become intense ... They make propaganda about damage (in Saudi ) which can be repaired in two weeks ... because America wants to conquer the region,” Rouhani said.

The president said he would introduce a regional peace plan dubbed HOPE (Hormuz Peace Endeavour) at the United Nations General Assembly this week.

“All countries of the Persian Gulf and the Strait of Hormuz and the United Nations are invited to join,” Rouhani said before leaving for New York to attend the annual gathering of world leaders at the United Nations.