Iran threatened on Saturday to block a corridor planned in the Caucasus under a regional deal sponsored by U.S. President Donald Trump, Iranian media reported, raising a new question mark over a peace plan hailed as a strategically important shift.

Language in the "peace deal" will give the U.S. exclusive rights to develop a key transit route that will be named after Trump.

Residents and politicians in Armenia and Azerbaijan are responding with cautious hope after their leaders signed a U.S.-brokered agreement aimed at ending decades of hostilities