Erdogan's spokesman Ibrahim Kalin added: "Turkey is not in favour of an economic war with anyone but when attacked ... will take all necessary steps".
"Turkish-Qatari relations are based on solid foundations of true friendship and solidarity", he said.
Turkey retaliated on Wednesday with tariffs on certain U.S. goods.
"The US is our major trade partner but it's not the only one", Pekcan, the trade minister, was quoted as saying by the official Anadolu news agency.
He said relations with Qatar, which he described as a "friendly and brotherly country", would be boosted in many areas.
Moves by the central bank to ensure Turkish banks have liquidity and a planned conference call by Turkish Finance Minister Berat Albayrak, who is Erdogan's son-in-law, on Thursday have gone some way to giving reassurance to investors.
A calculation by Bloomberg shows the items listed in the decree accounted for $1 billion of imports a year ago, similar to the amount of Turkish steel and aluminum exports that were subjected to higher tariffs by President Donald Trump last week.
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A source close to Franklin told TMZ Monday that those in her inner circle were told two weeks ago that " she could go anytime ". Franklin cancelled planned concerts earlier this year after she was ordered by her doctor to stay off the road and rest up.
Tensions between the two North Atlantic Treaty Organisation allies have been strained amid Turkey's detention of an American pastor and other diplomatic actions.
In response, Erdogan has called for a boycott of USA electrical goods while Ankara has sharply hiked tariffs on some U.S. goods.
The lira's fall had raised fears Turkey was on the verge of a fully-fledged economic crisis, especially in its banking system, that could spill over into Europe and other markets.
Turkey and Qatar have traditionally maintained good ties.
According to Al Shafi, Qataris have recently bought tens of millions of dollars' worth of Turkish lira with a view to supporting the Turkish economy.
Through his facebook and twitter official pages, the Egyptian-American businessman and chief economic adviser at Allianz, Mohamed A. El-Erian, posted that Qatar's support to Erdogan's government will help Turkey find alternative sources of support to avoid International Monetary Fund.
Ankara stood by Doha after Saudi Arabia and other Arab states severed diplomatic, trade and travel ties with Qatar a year ago, accusing it of financing terrorism, a charge Doha denies.