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.

The leaders of Armenia and Azerbaijan shook hands as they joined President Donald Trump at the White House on Friday for a peace summit where they signed an agreement aimed at ending decades of conflict.

WASHINGTON (Reuters) -Azerbaijan and Armenia signed a U.S.-brokered peace agreement on Friday during a meeting with U.S. President Donald Trump that would boost bilateral economic ties after decades of conflict and move them toward a full normalization of relations.