A US envoy has said the United States could strike Iran as soon as this weekend. The warning stacks on top of mounting threats coming out of both Washington and Israel. Setting a weekend deadline gives Tehran little time and suggests diplomacy is running short. Any American attack on Iran would push an already tense confrontation into new territory. Countries across the region are watching closely, since a strike could draw retaliation beyond Iran's borders. Markets and shipping routes usually react fast when talk of action against Iran hardens. It remains unclear whether the envoy's timeline is a pressure tactic or a genuine countdown. What is clear is that Washington and Tehran are now trading words with a clock attached.