US President Donald Trump threatened in an expletive-laden post on Sunday to strike Iran's power plants and bridges if it does not reopen the vital Strait of Hormuz, after announcing the rescue of an airman in a "miraculous" operation.
The war, which erupted on 28 February with US-Israeli strikes on Iran, has engulfed the Middle East and convulsed the global economy.
Iran has virtually blocked the Strait of Hormuz shipping lane, a vital conduit for oil and gas, and launched strikes on Israel and its Gulf neighbours.
Trump warned Iran to stop choking traffic through Hormuz. "Open the Fuckin' Strait, you crazy bastards, or you'll be living in Hell," he said, in his social media post. JUST WATCH!," Trump said, ending his Easter morning post with: "Praise be to Allah."
"Tuesday will be Power Plant Day, and Bridge Day, all wrapped up in one, in Iran. There will be nothing like it!!!" he declared. Later, Trump told Fox News that he believed there was a "good chance" that Iran would agree to a deal on Monday.
Trump's warning came as the Omani and Iranian deputy foreign ministers reportedly held talks on easing passage through Hormuz.
Many residents of Tehran seemed indifferent to Trump's threats.
In a large park in the west of the city, a group of young Iranians were having a picnic. Nearby, two friends were playing with a frisbee as techno music blared from a portable speaker.
One man was making the most of a windy day by flying his kite in front of the Milad Tower, an iconic landmark of Tehran. 'Choose peace' Critical infrastructure across the Gulf came under attack from Iran again on Sunday, with damage reported at civilian facilities in the United Arab Emirates, Bahrain and Kuwait.
Pro-Iran armed groups also carried out two attacks on US diplomatic sites in Iraq overnight, the US embassy in Baghdad said.
On another front, Lebanon has increasingly been drawn into the conflict since the Iran-backed Hezbollah group began targeting Israel.
Israel has struck back and pushed its ground forces into southern Lebanon.
A source from the Lebanese civil defence told AFP that an Israeli strike on southern Lebanon's Kfar Hatta killed a family of six waiting to evacuate and a relative who had come to pick them up.
Another Israeli strike on south Beirut killed at least four people, the Lebanese health ministry said.
The war has cast a pall over Easter Sunday celebrations for Christian minorities in Lebanon and across the region.
In the usually lively alleyways of Jerusalem's Old City, silence reigned on Sunday.
As a security precaution, Israeli authorities have restricted access to the Holy Sepulchre, where the faithful commemorate Christ's crucifixion and resurrection.
"It's very hard for all of us because it's our holiday... It's really hard to want to pray but to come here and find nothing. Everything is closed," said Christina Toderas, 44, from Romania.
In his Easter blessing at the Vatican, Pope Leo XIV urged "those who have the power to unleash wars" to "choose peace" instead and criticised global indifference to "the deaths of thousands of people". Bushehr nuclear plant In Iran, a strike near the Bushehr nuclear plant on Saturday killed a guard and led Russia, which partly constructed the facility and helps operate it, to announce it was evacuating 198 workers and to condemn the strike as "an evil deed".
Iranian Foreign Minister Abbas Araghchi warned that continued attacks on the plant on the southern coast could eventually lead to radioactive fallout that would "end life in GCC (Gulf Cooperation Council) capitals, not Tehran". Bushehr is considerably closer to Kuwait, Bahrain and Qatar than it is to the Iranian capital.
Against the backdrop of war, Iran has kept up a crackdown weeks after it quelled a massive wave of anti-government protests, with the judiciary announcing the execution of two men convicted of acting on behalf of Israel and the United States.
On Sunday, communications monitor Netblocks said Iran's internet blackout was now the longest nationwide shutdown in history.