Turkey and the United States squabbled last week over Turkey's failure to free a US pastor named Andrew Brunson from house arrest while he awaits his trial on terrorism charges.
Turkey and the USA are in jeopardy, Turkish President Recep Tayyip Erdogan said, warning the White House he would turn to "new allies" if the United States continues to show a "lack of respect" for his country.
Friday evening, the U.S. issued a proclamation officially announcing the doubling of steel tariffs on Turkey, planned to go into effect Monday, according to worldwide media reports.
Tariffs on Turkish aluminum are to be increased to 20 percent and steel tariffs are to be moved up to 50 percent, according to Trump.
We look the issue straining relations between the U.S. and Turkey.
On Friday, the currency dropped as much as 18 percent at one point, the biggest one-day fall since a 2001 financial crisis in Turkey.
All eyes will be on the lira when foreign exchange markets reopen on Monday after the weekend break.
The new duties on Turkey are double the level that Trump imposed in March on steel and aluminium imports from a range of countries.
"The aim of the operation is to make Turkey surrender in all areas, from finance to politics", said Erdogan on Sunday. "We've stood with neighbors before, and will again now". "With God's permission we will overcome this", Erdogan told his party members in the Black Sea city of Trabzon.
"These are the bullets, cannonballs and missiles of an economic war waged against our country", he said.
"We are never accepting this order which declared economic war to the entire world and which held countries to ransom through sanction threats", he added, referring to the USA administration.
"Some close the doors and some others open new ones", added Erdogan, who has built closer ties over the last years with countries from Latin America, Africa to Asia.
Turkey's President Erdogan's speech next on tap.
He further added that the only response to a country which chooses to sacrifices its strategic partnership and a half century alliance with a state with a population 81 million for the sake "terror groups" is "good-bye".
Mr Erdogan has linked Gulen's fate to that of American Christian pastor Andrew Brunson, who is on trial in Turkey on terrorism charges for allegedly supporting a group that Ankara blames for the failed coup.
Turkish officials held talks in Washington this week, but there was no breakthrough.
Analysts say that while Washington's sanctions against Ankara sparked the immediate crisis, Turkey's economy has been risking trouble for a while due to high inflation and the weak lira.
He also branded interest rates as a "tool of exploitation" which should be kept as low as possible.
President Erdogan urged his people in a counter-tweet: "Change the euros, the dollars and the gold that you are keeping beneath your pillows into lira at our banks".
"You arrest my Halkbank general deputy director?"
U.S. State Department spokesperson Heather Nauert said Thursday that Washington "would define progress as Pastor Brunson being brought home".