By Agencies

After Turkish president urges people to support currency, US counterpart adds pressure with doubling of metals' tariffs.

US President Donald Trump has announced a doubling of steel and aluminum tariffs on Turkey, piling economic pressure on the NATO ally after its currency went into a tail-spin.

Trump's announcement on Friday came hours after Turkish President Recep Tayyip Erdogan lashed out against a shadowy international "interest rate lobby" which, he suggested, was "campaigning" to harm Turkey's economy, after the lira fell more than 14 percent overnight.

Turkey's currency extended its losses following Trump's statement, falling 19 percent daily against the US dollar amid growing worries about worsening US relations.

Washington has been pushing Ankara to release an American pastor, who's being held on terrorism charges.

Earlier this week, Erdogan ordered the asset freeze of two US officials in retaliation for sanctions imposed on Turkey's justice and interior ministers over the detention of an Evangelical Christian pastor Andrew Brunson.

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! Aluminum will now be 20% and Steel 50%. Our relations with Turkey are not good at this time!

— Donald J. Trump (@realDonaldTrump) August 10, 2018

At 13:35 GMT, the Turkish lira was down 19 percent at 6.6 against the US dollar. Shares of European lenders also dropped earlier in the day, amid concerns about their Turkey exposure.

But a defiant Erdogan brushed aside concerns, telling a roaring crowd of Turks in the Black Sea city of Rize not to worry. 

"There are several campaigns being carried out [against Turkey]. Do not heed them," Erdogan said.

"If they have their dollars, we have our people, our God.

"Know this: We are better than yesterday, we will be even better tomorrow. Have no doubts about it," he added.

He also renewed a call for Turks to exchange gold and dollars into the local currency, framing Turkey's currency crisis as a "national battle" against economic enemies.

"The dollar cannot block our path," Erdogan told a crowd. 

"However, I say it once again from here. If there is anyone who has dollars or gold under their pillows, they should go exchange it for liras at our banks. This is a national, domestic battle." 

Erdogan, a self-described "enemy of interest rates", wants cheap credit from banks to fuel growth, but investors fear the economy is overheating and could be set for a hard landing.

Despite the turmoil, Turkey became the fastest-growing country in the world last year, with an economic growth rate of 7.4 percent, according to the government.