US President Donald Trump Mr Trump announced on Twitter last week that he had authorised a doubling of duties on aluminium and steel imported from Turkey, putting unprecedented economic pressure on Ankara.
"They should have given him back a long time ago, and Turkey has in my opinion acted very, very badly", Trump told reporters at the White House.
A senior United States official told CNN that in exchange for Turkey's release of Brunson, Israel agreed to release Ebru Ozkan, a 27-year-old Turkish woman held in Israel on suspicion of aiding Hamas, the Palestinian militant group that controls Gaza.
Turkey retaliated with some $533 million of tariffs on some U.S. imports - including cars, tobacco and alcoholic drinks - and said it would boycott USA electronic goods.
Trump then called Brunson a "very innocent man" and said his arrest was "not fair, not right".
Last month, at Brunson's third court hearing in almost two years, U.S. officials thought they had brokered a deal to free him by pressuring Israel to release a Turkish citizen imprisoned there.
The Turkish lira has strengthened more than 3% today, ahead of a presentation by Finance Minister Berat Albayrak to investors, shrugging off USA comments ruling out the removal of steel tariffs on Turkey even if it frees a United States pastor. We are not going to take it sitting down. It hit an all-time low of 7.2 lira to the dollar earlier in the week.
The United States was the fourth-largest source of imports to Turkey past year, accounting for $12 billion of imports, according to International Monetary Fund statistics.
Americans with a bit of common sense see that what is being done to Turkey is not only penalizing the Turkish people and plunging relations into a state of collapse, but it is also hurting global American security interests as well as the US economy.
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.
In a bid to soothe the markets, Turkish Finance Minister Berat Albayrak went on record on Thursday to reassure investors that Ankara was still in control.
Three big companies operating in Dogubank, a trade center specialized in the sales of electronic products in central Istanbul, suspended 50 million USA dollars' worth of iPhone orders, the Turkish daily said.