Teheran vows to reduce commitments to 2015 nuclear deal with world powers

The United States enacted a new round of sanctions on Monday, targeting Iran's supreme leader and some senior officials, further escalating tensions between the two sides.

US President Donald Trump signed an executive order on Monday, saying he is "imposing hard-hitting sanctions on the supreme leader of Iran and the office of the supreme leader of Iran and many others".

Trump accused Iran's Supreme Leader Ayatollah Ali Khamenei of being ultimately "responsible for the hostile conduct" of the country.

In response, Iranian President Hassan Rouhani said on Tuesday that the fresh sanctions prove that Washington is lying about seeking to hold talks with Teheran.

"At the same time as you call for negotiations you seek to sanction the foreign minister? It's obvious that you're lying," Rouhani said.

Iranian Secretary of the Supreme National Security Council Ali Shamkhani said on Tuesday that his country on July 7 will take steps to reduce its commitments under the 2015 nuclear deal with world powers, reported Reuters, citing Fars news agency.

But US National Security Adviser John Bolton has said Washington was still willing to talk to Iran.

"All that Iran needs to do is to walk through that open door," he said.

The new sanctions will deny Iranian leadership's access to financial resources, blocking from using the US financial system or accessing any assets in the US, White House said.

US Treasury Secretary Steven Mnuchin revealed on Monday that the new order will freeze billions of additional dollars in Iranian assets.

He also said Trump had instructed him to designate Iranian Foreign Minister Mohammad Javad Zarif "later this week".

Meanwhile, Iran's Foreign Ministry spokesman Abbas Mousavi tweeted on Tuesday that Trump's action means the permanent closure of the path of diplomacy, and the US is destroying all the established international mechanisms for maintaining the world peace and security.

Majid Takht Ravanchi, Iran's ambassador to the United Nations, said on Monday that the new sanctions serve "to reflect Washington's disrespect for the international law".

Zou Zhiqiang, a researcher at the Middle East Studies Institute of Shanghai International Studies University, said the US decision is not wise and will make the tension even more difficult to solve.

He called the new sanctions retaliatory actions in response to Iran's recent actions, including shooting down a US drone.

Iran's Revolutionary Guard Corps said last week it had shot down a US unmanned drone. Teheran insisted the shoot happened when the drone entered Iran's airspace near the Mobarak Mountain region in southern coastal Hormozgan Province. But the US said it had been flying over international waters.

"The US wants to fight back but also has fear of losing the control of the situation, so it chose to impose more sanctions," he said. "But, meanwhile, the space and ways of adding new sanctions is not enough."

Zou said the sanctions against Khamenei are more symbolic and show the tough stance of the US, but the actual effect is limited.

However, he said the sanctions aimed directly at Iranian supreme leader aggravated the hostility of both sides, and will undoubtedly arouse greater reaction from Iran.

Xinhua and AFP contributed to this story.