US President Donald Trump has said he could impose additional tariffs on countries that continue to trade with Iran, in an executive order signed on Friday. The order does not specify the rate that could be imposed, but uses 25% as an example, and states it will apply to any goods imported into the US from countries that buy or acquire goods or services from Iran.

While Trump has not directly commented on the executive order's details, he reiterated his stance of demanding 'no nuclear weapons' for Iran during a flight on Air Force One. This development coincides with ongoing discussions between US and Iranian officials in Oman, amidst heightened tensions and threats from both sides.

Earlier this year, Trump had threatened a similar 25% tariff on countries engaging in business with Iran, posting on social media that any such country doing business with Iran would face tariffs on all dealings with the United States. However, specific details on the implementation of these tariffs have been sparse.

The White House declared this executive order as part of an ongoing 'national emergency' concerning Iran, linking the country’s actions with nuclear development and support for terrorism to threats against American security and interests.

Iran has not yet responded publicly to the order. Amid the executive order's announcement, US-Iran talks in Oman have been characterized as 'very good' by Trump, who noted that Iran seems eager to reach an agreement. If negotiations fail, he warned that the consequences could be severe.

The discussions mark the first engagement between US and Iranian officials since a bombardment of Iran’s nuclear facilities last June, indicating both countries' willingness to explore avenues of negotiation despite mounting pressure and calls for military action.