Iran and the United States are sliding rapidly towards military conflict as hopes fade for a diplomatic solution to their standoff over Tehran’s nuclear program, officials on both sides and diplomats across the Gulf and Europe say. Iran’s Gulf neighbors and its enemy Israel now consider a conflict to be more likely than a settlement, these sources say, with Washington building up one of its biggest military deployments in the region since the invasion of Iraq in 2003.

Tensions escalate in West Asia as the U.S. and Iran bolster military presence amid looming decisions on potential strikes.

The Iranian leadership is weighing up whether resisting US demands is the best option for its survival.