After 21 hours of marathon talks in Islamabad, the United States and Iran have walked away without reaching an agreement.

U.S. Vice President JD Vance described the proposal put to Tehran as Washington’s “final and best offer,” but discussions ultimately broke down over Iran’s refusal to commit to not developing nuclear weapons.

The failure to secure a deal raises fresh questions about regional stability and the future of diplomatic efforts to contain Iran’s nuclear ambitions.

And now US President Donald Trump says the navy will block the Strait of Hormuz. 

Jeffery Pryce, Senior Fellow at the Foreign Policy Institute at Johns Hopkins School of Advanced International Studies, told Mike Hosking there's no knowing what will happen next. 

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