Iran said on Monday President Hassan Rouhani will not meet with U.S. President Donald Trump at the United Nations, a day after the White House left open the possibility of talks between them. 

"Neither is such an event on our agenda, nor will it happen. Such a meeting will not take place," Foreign Ministry spokesman Abbas Mousavi said in remarks carried by state TV.  

"As we have stated before, if the Americans return to the JCPOA and cease their economic terrorism, they can return to the joint commission and talk," Mousavi added. 

Iranian officials have repeatedly rejected a meeting and any talks with Washington while Iran is subject to sanctions, which Trump reimposed after withdrawing last year from Tehran’s 2015 nuclear accords with world powers. 

Iran earlier condemned as "unacceptable" U.S. accusations it was behind an attack on Saudi oil plants, after the United States said it was "locked and loaded" for a potential response.  

China on Monday also responded that "in the absence of firm conclusions, it is irresponsible to assume who should be responsible," amid the recent "blame war" between the U.S. and Iran. 

"Stopping all sanctions is an indispensable precondition for constructive diplomacy. We hold meetings when we are sure that our people’s problems can be solved," Iranian government spokesman Ali Rabiei said, according to media outlet Tasnim. 

"Sanctions must be lifted, and the United States must respect the Iranian nation," Rabiei said. 

White House adviser Kellyanne Conway said on Sunday the previous day’s attacks "did not help" prospects for a meeting between the two leaders during the United Nations General Assembly this month, but she left open the possibility a meeting could take place. 

(With input from Reuters, AFP)