Ayatollah Mojtaba Khamenei, Iran’s supreme leader, delivered a sweeping rebuke to U.S. policy on Thursday, warning that Tehran would never surrender its nuclear and missile capabilities and that American forces had no legitimate presence in the Persian Gulf. The comments, read by a state television presenter in a speech marking Iran’s Persian Gulf Day, were Khamenei’s first public remarks since he succeeded his father, Ayatollah Ali Khamenei, who was killed in the airstrikes that opened the U.S.-led war.

“Ninety million proud and honorable Iranians, at home and abroad, regard all of Iran’s identity-based, spiritual, human, scientific, industrial and technological capabilities — from nanotechnology and biotechnology to nuclear and missile capabilities — as national assets and will protect them just as they protect the country’s waters, land and airspace,” Khamenei said, according to AP.

Referring to the United States as “the Great Satan,” an epithet used by Iranian leaders since the 1979 Islamic Revolution, Khamenei said: “Foreigners who come from thousands of kilometers away to act with greed and malice have no place in it, except at the bottom of its waters.” The cleric, who was reportedly wounded in the Feb. 28 attack that killed his father, has not been seen in public since assuming power.

His defiance came as Brent crude oil prices soared to $126 a barrel on Thursday, fueled by Iran’s continued closure of the Strait of Hormuz. The narrow waterway, which Iran controls jointly with Oman under international law that traditionally treats it as an open transit route, carries about one-fifth of the world’s traded crude. Tehran has been charging some vessels $2 million to pass, a practice denounced by the United Arab Emirates and other Gulf Arab states as piracy.

The Trump administration is weighing a new diplomatic and economic push to loosen Iran’s grip. A senior U.S. official, speaking on condition of anonymity to discuss internal deliberations, said the plan would keep the naval blockade on Iranian ports in place while pressing allies to impose higher costs on any Iranian move to disrupt energy flows. The proposal, first reported by The Wall Street Journal, is the latest effort by Washington to persuade other nations to help reopen the strait, a crucial export route for Gulf allies.

Pakistan, which has been hosting indirect talks between the two foes, said Thursday that it would welcome direct contact between the parties, even by telephone. “If both sides can engage in real-time talks, that could ease friction points,” foreign ministry spokesperson Tahir Andrabi told a weekly press conference, though he declined to disclose details of any specific proposals.

Domestically, Iran’s government has intensified a crackdown on dissent, announcing the execution of Sasan Azadvar, a 21-year-old man convicted of “cooperating with the enemy by attacking police officers” during nationwide protests in January. The Mizan news agency reported he was hanged on Thursday. Volker Turk, the U.N. high commissioner for human rights, said Wednesday that at least 21 people have been executed since the war began, including nine linked to protests and ten for alleged membership in opposition groups. At least two others were hanged on espionage charges. Rights groups say trials are routinely held behind closed doors with no opportunity for the accused to challenge the charges, and that several more people remain at risk of execution.