Andrew Brunson, the newly released US Pastor has met with Donald Trump at the White House after two years' detention in Turkey.
The evangelical pastor thanked Trump and his administration before praying with the president in the Oval Office.
Trump said Brunson's release will be a "tremendous" step in US Turkish relations and re-thanked Turkey's President Erdogan for releasing the Pastor.
However, the US president denied earlier reports by NBC News and the Washington Post that he had cut a deal with Ankara.
Trump wrote in a Tweet: "I don't make deals with hostages".
The Pastor had been under house arrest since July and had lived in Turkey for more than 20 years.
Brunson was accused of having links to Kurdish militants and supporters of Fethullah Gulen, the US-based cleric blamed by Erdogan's government for a failed coup in 2016. The Pastor denied the charges brought against him and his detention.
On Friday, a Turkish court sentenced Brunson to three years in prison but released him because of the time he had already spent in detention.
Brunson's detention soured an already strained relationship between the two NATO allies, with both nations imposing sanctions on the other earlier this year. Tukey's economy nosedived due to the tariffs and concerns over Erdogan's grip on monetary policy.
Turkey is against US support for the YPG Kurdish fighters in Syria, which it labels as a terrorist group, as well as Turkey's plans to buy a Russian missile defense system.
President Erdogan wrote on his Twitter account: "I hope that the United States and Turkey will continue their cooperation as the allies that they are, and fight together against terrorist groups".
In his tweet urging joint action against so-called terrorist groups, Erdogan included the Kurdistan Workers' Party (PKK) militant group and a network of Gulen's supporters that it accuses of trying to overthrow the government.
Meanwhile, US officials also called on Turkey to also release a Turkish-US national and former NASA scientist in jail on terrorism charges, as well as three local employees of the US consulate who have also been detained.