Trump has 'no intention' of meeting with Iranians in New York

US President Donald Trump has said he has no intention of meeting Iranian officials on the sidelines of the UN General Assembly in New York this week.

"Nothing is ever off the table, but I have no intention of meeting with Iran," Trump said as he was leaving Washington for Texas, albeit stressing that he remained "flexible."

Iranian Foreign Minister Mohammad Javad Zarif is already in New York, and has given an interview to CBS News in which he denied that Tehran was behind a recent attack on a Saudi Arabian oil plant.

"We are confident that if the United Nations carries out an impartial investigation the outcome will be that it was not launched from Iran," Zarif said, according to a transcript of the interview, due due to air later Sunday. "They were not Iranian backed attacks."

Trump last week slapped new sanctions on Iran, including targeting the central bank.

The administration has been re-imposing sanctions for a year, ever since Trump unilaterally withdrew from a 2015 nuclear deal with Iran and world powers. The sanctions, especially on the oil and financial sectors, have been badly hurting Iran's economy.

The president has also sent more troops to build up air and missile defences around Saudi Arabia and the United Arab Emirates.

Zarif said the dispatch of forces was "posturing" and that it would not help. The top Iranian diplomat called for an end to the Saudi-led war in Yemen.

Iranian-backed Houthi rebels in Yemen claimed the oil plant attack, but the US suspects that Iran is behind them.