US President Donald Trump has issued a fresh and direct warning to Iran, targeting Supreme Leader Ayatollah Ali Khamenei as nationwide anti-government protests intensify across the country. Signalling a hardening stance, Trump said Washington is considering "strong action" and confirmed that the US Army is closely monitoring the unfolding situation. He also did not rule out the use of force, raising fears of a potential escalation at a time when Tehran is facing its most serious internal unrest in years.