Iran nuclear deal moves to battleground of US Congress

Republican and Democratic hawks could derail historic agreement that will grant relief from sanctions in return for curbs on Iran's nuclear programme

The battle over the Iran nuclear agreement is set to move to Washington as the Obama administration begins a three-month campaign to stop the hard-won deal being derailed by congressional Republicans.

The deal - reached in a Vienna hotel early on Tuesday morning after prolonged talks between foreign ministers - binds Iran, the US, UK, France, Germany, Russia and China to a series of undertakings stretching over many years. Iran will dismantle much of its nuclear infrastructure, while the UN, US and European Union will remove a wall of sanctions built around Iran over the last nine years.