'I have just authorized a doubling of Tariffs on Steel and Aluminum with respect to Turkey as their currency, the Turkish Lira, slides rapidly downward against our very strong Dollar!' Trump said in an early morning post on Twitter.
The Turkish lira fell 13 percent to 6.51 per dollar.
Ahead of the USA data, Turkish President Erdogan's speech due at 1100 GMT could also fuel some fresh volatility around the European currency.
With the currency diving, Trump authorized higher tariffs on Turkish imports on aluminum and steel of 20% and 50% respectively.
"Turkey expects other member countries to abide by global rules", the country's trade ministry said in a statement. U.S. stocks were also rattled.
A delegation led by Turkish Deputy Foreign Minister Sedat Onal failed to secure a deal last Wednesday in talks in Washington on a number of issues including Brunson.
The president, who says a shadowy "interest rate lobby" and Western credit ratings agencies are attempting to bring down Turkey's economy, appealed to his countrymen's patriotism.
Hoping to put pressure on the North Atlantic Treaty Organisation ally to free the pastor, the White House sanctioned two top Turkish government officials. "Relations with countries who behave like this have reached a point beyond salvaging", said Erdogan, who warned of "economic war".
Although Mr Erdogan struck a defiant tone, his foreign ministry called for diplomacy and dialogue to solve problems with the US.
In a Friday opinion piece for the New York Times, though, he used a milder tone to restore ties before it is too late, reminding of long-standing relations the United States established with Turkey over half a century ago upon its accession into North Atlantic Treaty Organisation.
Brunson has been detained for the past 20 months on accusations that he supported groups the Turkish government deems terrorists.
"We can only say "good-bye" to anyone who sacrifices its strategic partnership and a half century alliance with a country of 81 million for the sake of relations with terror groups", he said.
Turkey wants the USA to extradite cleric Fethullah Gulen, a Pennsylvania-based cleric who Turkish authorities say masterminded the coup attempt in which 250 people were killed.
"If you pressure us through the dollar, we will look for other ways to carry out our works", he said. Gulen has denied the allegation.
His cause resonates with Trump's Christian conservative supporters, who could be influential as Republicans seek to retain control of Congress in midterm elections in November.
Turkey will "never accept the order, which declares war against the whole world", through the threats of sanctions, he said, referring to the U.S.
'We are once again facing a political, underhand plot.