Jeddah — US Secretary of State Mike Pompeo held talks Monday with Saudi leaders ahead of new sanctions on Tehran.

After meeting Custodian of the Two Holy Mosques King Salman, Pompeo tweeted that he had a productive meeting to discuss heightened tensions in the region and the need to promote maritime security in the Strait of Hormuz.

"Freedom of navigation is tantamount," he tweeted.

Pompeo also met Crown Prince Muhammad Bin Salman, deputy premier and minister of defense.

He was later due to hold talks in the United Arab Emirates, US officials said.

Pompeo described Saudi Arabia and the UAE as "two great allies in the challenge that Iran presents".

"We'll be talking with them about how to make sure that we are all strategically aligned and how we can build out a global coalition," Pompeo said.

He said the US sought a coalition "not only throughout the Gulf states but in Asia and in Europe that understands this challenge and that is prepared to push back against the world's largest state sponsor of terror".

US President Donald Trump has said he was ready to reach out to Iran if the country agreed to renounce nuclear weapons.

With the US out of the deal, Iran has said it would reduce some of its nuclear commitments unless the remaining partners -- Britain, China, France, Germany and Russia -- help it circumvent US sanctions and sell its oil.

Trump left that agreement more than a year ago and has imposed a robust slate of punitive sanctions designed to choke off Iranian oil sales and cripple its economy -- which he now plans to expand.

"We are putting major additional Sanctions on Iran on Monday," tweeted Trump, who has also deployed additional troops to the Middle East.

"I look forward to the day that Sanctions come off Iran, and they become a productive and prosperous nation again - The sooner the better!"

But in a show of defiance, Iran's foreign ministry said Monday the new sanctions would have no "impact".

"We really do not know what (the new sanctions) are and what they want to target anymore, and also do not consider them to have any impact," ministry spokesman Abbas Mousavi said at a press conference in Tehran. — Agencies