Iran has said it is confident it can counter widened US sanctions after Washington announced what it described as an “economic D-Day” against the country to try to isolate it from the global economy.

Iranian Economy Minister Ali Madanizadeh said Tehran was “fully prepared” for the sanctions, which he said would lead to “another defeat” for the US.

Announcing a raft of new measures, US Treasury Secretary Scott Bessent said any nation financially partnering with Iran would be isolated, and that banks and businesses dealing with Iran would share its isolation if they refused to cut ties.

The latest moves follow U-turns and extended deadlines from the White House in its efforts to end the conflict.

Bessent described the new measures as “the single greatest financial offensive ever” against Iran, which would “tighten the noose and block every potential source of revenue”.

Iran’s largest trading partners include China, Turkey and the United Arab Emirates – which announced last week it was halting all trade and financial transactions with Tehran.

But hours after the US announcement, Iran said it was confident its trading partners would continue to do business.

Madanizadeh said neither China nor Russia had “accepted” the US measures, and predicted other countries would resist them.

“The government is and was ready and has a two-year plan to manage these events,” he told state television, adding that Tehran had been “waiting for these plans for a long time”.

“We also have our own tools and know how to play the game,” he said.

The Chinese Foreign Ministry said sanctions and pressure tactics did not help and Beijing would do what was necessary to protect China’s interests.

The war has led to hikes in global oil prices, and in response to the latest threat Iran warned it would shut down all oil exports from the region if the war continued.

The Iranian regime has also issued a fresh warning to ships not to pass through the Strait of Hormuz without permission, according to Reuters.

One fifth of the world’s oil and gas usually passes through the strait – a narrow waterway south of Iran. But the flow has been effectively blocked by the country since the conflict began at the end of February, leading to higher oil prices globally.

At a press conference earlier on Monday outlining what has been called “Operation Economic Outcast”, Bessent said the US was launching an “economic onslaught against Iran’s financial connections around the globe”.

“Iran now faces a very clear choice with only two paths before them: complete global isolation… or a path back to normalcy with an opportunity to rejoin the global economy,” he said.

The treasury secretary claimed America was “no longer managing the Iranian threat, we are ending it”.

Bessent said the Treasury had mapped networks, facilitators and financial channels used by Iran to evade sanctions to trade oil.

The department said it had issued determinations against five sectors: digital assets, technology, gold, aviation and shipping. The Treasury has also imposed sanctions on almost 60 entities, individuals and vessels.

In a warning to governments and entities assisting or trading with Iran, he said they could not “claim they are blind to enabling this activity”.

He declined to highlight specific countries, but said Trump would be phoning world leaders “with specific requests to cease their interactions with the regime”.

While he said it was important to give people time to understand the new sanctions, he added: “They should know that we will move very quickly and that we are serious.”