As Washington abandons talks with Iran for an aggressive economic pressure campaign, a cornered Tehran is now threatening military escalation and a wider war to force negotiators back to the table.

US President Donald Trump has dismissed diplomacy with the Islamic Republic, calling a June ceasefire agreement one that “isn’t worth the paper it’s written on.” His administration has instead piled pressure on Iran through a global sanctions campaign, military strikes and a maritime blockade that stops goods from leaving or entering the country.

The multifront campaign has put Iran under unprecedented pressure, forcing its fatigued population to endure still more strain. Iranian Supreme Leader Mojtaba Khamenei, meanwhile, remains conspicuously absent. Tuesday will mark his sixth month in hiding in an attempt to avoid the fate of his father and predecessor, Ayatollah Ali Khamenei, who was killed in an airstrike at the start of the US-Israeli war against Iran in late February.

Iran’s military officials are increasingly touting new tactics in response to the pressure, threatening to target nations taking part in the blockade and warning that they could broaden the conflict.

On Monday, a wave of attacks from the Iran-backed Houthi rebels in Yemen hit several Saudi towns and cities, wounding at least 73 civilians and causing fires at energy facilities. Global oil prices climbed 1%.