Turkey's government has raised tariffs on United States imports, including passenger cars, tobacco and alcohol, Official Gazette said this morning.
U.S. President Donald Trump authorised the implementation of higher tariffs on aluminium and steel imports from Turkey last Friday.
The turmoil has raised fears of a looming economic crisis in Turkey and prompted alarm that foreign investors in the country, including Qatar, could be hit in the fallout.
Turkish Vice President Fuat Oktay said that the tariff hikes were ordered "within the framework of reciprocity in retaliation for the conscious attacks on our economy by the USA administration".
The tariff increases amount to a doubling of the existing rate, the state-run Anadolu news agency said, in an apparent parallel response to Trump's move.
Commenting on the move, the USA leader said: "I have just authorised a doubling of tariffs on steel and aluminium with respect to Turkey as their currency, the Turkish lira, slides rapidly downwards against our very strong dollar".
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Worldwide benchmark Brent crude traded at around $72.80 on Friday morning, little changed from the previous session, while U.S. While taking stock of the recent developments, the direction of oil prices is likely to be on the road south in near term.
In recent days, Qatari supporters of Turkey have begun a public campaign in Doha to change their riyals into lira in an attempt to shore up the plunging Turkish currency.
"Qatar has pledged $15 billion of direct investments in Turkey", presidential spokesman Ibrahim Kalin wrote on Twitter.
Qatari Ambassador to Turkey Salem bin Mubarak Al Shafi said his country would continue supporting Turkey following recently-imposed US sanctions on the country.
But many analysts say the only way for the authorities to show they are really serious about tackling Turkey's economic problems - which include inflation approaching some 16 percent - would be a sharp interest rate hike.
"President Erdogan appears to be playing a risky game if he thinks he can come out on top in this spat with the USA", he commented.
Qatar's royal court released a statement saying Al-Thani "issued directives that will see the State of Qatar to provide a host of economic projects, investments, and deposits" worth $15 billion to support the Turkish economy.