Iran said the U.S.’s blockade of its ports is “doomed to fail” as oil prices remain elevated and the Strait of Hormuz closed.

Tehran remains defiant as hostilities continue, and Iranian Supreme Leader Mojtaba Khamenei released a statement claiming the future of the Persian Gulf will be one “without America.”

The statement, read by Iranian state-run media as Khamenei continues to not be seen since the beginning of the war, added that the country “will guard” its nuclear and missile technologies.

The stance continues to clash with that of the U.S. and President Donald Trump, who said on Wednesday he is maintaining the blockade of Iranian ports until a deal that addresses the U.S.’s concerns about the country’s nuclear program is reached.

Speaking to Axios, Trump said he rejected an Iranian proposal to end the war and reopen the Strait of Hormuz without a nuclear deal. He said the ongoing blockade is “somewhat more effective than the bombing.”

“They are choking like a stuffed pig. And it is going to be worse for them. They can’t have a nuclear weapon,” Trump said. “They want to settle. They don’t want me to keep the blockade. I don’t want to [lift the blockade], because I don’t want them to have a nuclear weapon,” he added.

Trump claimed that Tehran’s oil storage facilities and pipelines are “getting close to exploding” because the country can’t ship exports as a result of the blockade.

The outlet also cited three sources who said the U.S. Central Command (CENTCOM) has prepared a “short and powerful” wave of renewed strikes hoping to break the deadlock.

Iran, in turn, has threatened “unprecedented military action” if the U.S. continues with the blockade.

Citing an unnamed official, Iranian state-run press said its leaders’ “patience has limits” and a continued blockade would warrant a “punishing response.”

“The official warned that the enemy should soon expect a different kind of response,” the report added, without offering any additional details.

Oil prices kept rising as the standstill continues. Brent crude oil topped $124 per barrel on Wednesday before pairing gains over the next hours, standing at over $114 at 8:15 a.m. ET on Thursday. The price of West Texas Intermediate also dropped on Thursday, falling below $105 a barrel.