DUBAI/tehran, May 1 -- Iran's supreme leader said on Thursday that the Islamic Republic will protect its "nuclear and missile capabilities" as a national asset, likely seeking to draw a hard line as US President Donald Trump seeks a wider deal to cement the shaky ceasefire now holding in the war. Ayatollah Mojtaba Khamenei, speaking in a written statement read by a state television anchor as he has since taking over as Iran's supreme leader, struck a defiant tone, insisting the only place Americans belonged in the Persian Gulf is "at the bottom of its waters" and that a "new chapter" was being written in the region's history. However, his remarks come as Iran's oil industry has begun to be squeezed by a US Navy blockade halting its oil tankers from getting out to sea. Meanwhile, benchmark Brent crude for June delivery reached as much as $126 a barrel in trading on Thursday as Iran maintains its chokehold on the Strait of Hormuz, the narrow mouth of the Persian Gulf through which a fifth of all crude oil and natural gas traded passes. All this is putting additional pressure on the world's economy as Trump likely weighs how to respond. "By God's help and power, the bright future of the Persian Gulf region will be a future without America, one serving the progress, comfort and prosperity of its people," Khamenei said. He reportedly was wounded in the February 28 attack that killed his father, the 86-year-old Supreme Leader Ayatollah Ali Khamenei. "We and our neighbours across the waters of the Persian Gulf and the (Gulf) of Oman share a common destiny. Foreigners who come from thousands of kilometres away to act with greed and malice there have no place in it - except at the bottom of its waters." With a fragile ceasefire in place, the US and Iran are locked in a standoff over the strait. The USblockade is designed to prevent Iran from selling its oil, depriving it of crucial revenue while also potentially creating a situation where Tehran has to shut off production because it has nowhere to store oil. The strait's closure, meanwhile, has put pressure on Trump, as oil and gasoline prices have skyrocketed ahead of crucial midterm elections, and it has pressured his Gulf allies, which use the waterway to export their oil and gas. A recent Iranian proposal would push negotiations on the country's nuclear programme to a later date. Trump said one of the major reasons he went to war was to deny Iran the ability to develop nuclear weapons. Iran long has maintained its program is peaceful, though it enriched uranium at near-weapons-grade levels of 60%. Speaking to mark Persian Gulf Day in Iran, Khamenei's remarks signalled that nuclear issues and Iran's ballistic missile programme wouldn't be traded away. "Ninety million proud and honourable Iranians inside and outside the country regard all of Iran's identity-based, spiritual, human, scientific, industrial and technological capacities - 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. He referred to America as the "Great Satan", a long hurled insult by Iranian leaders towards the US since the 1979 Islamic Revolution. In his remarks, Khamenei seemed to signal Iran would maintain its control over the waterway, which sits in the territorial waters of Iran and Oman. Iran had been charging some ships reportedly $2 million apiece to travel through the strait. He said that Iran's control of the Strait of Hormuz will make the Gulf more secure, and that Tehran's "legal rules and new management" of the strait will benefit all the region's nations. Iran's President Masoud Pezeshkian on Thursday said a US naval blockade of Iranian ports would deepen disruptions in the Gulf and fail to achieve its objectives."Any attempt to impose a maritime blockade or restrictions is contrary to international law... and is doomed to fail," Pezeshkian said. He added that such measures would "not only fail to enhance regional security, but are in fact a source of tension and a disruption to lasting stability in the Persian Gulf". The US imposed a naval blockade on Iran's ports and coasts on April 13, days after a ceasefire paused its war with Iran. Iran's military has kept shut the strategic Strait of Hormuz, a vital conduit for global oil and gas shipments, and recently threatened to "respond" if the US blockade continued....