The United States recently decided to impose duty fees on imports from Turkey due to a political disagreement. An American citizen is detained in Turkey under accusations that he participated in a coup against President Erdogan in 2016, which is what motivated the US to use tariffs as a negotiation tactic. Representatives from Turkey were supposed to travel to the United States in order to properly discuss the issue.
Right now it appears that the negotiations between the two countries are not producing results quickly enough. Earlier today President Erdogan announced that Turkey will boycott US-made electronics such as cellphones and computers, and would favor items produced by their Asian competitors or even local Turkish manufacturers.
Meanwhile, the Turkish lira, which has now officially dropped by 40% in 2018 alone, managed to stabilize a little today on statements from the Turkish government that they will take steps to control the crisis. It is yet unclear if the central bank will be allowed to hike interest rates, however.