Recep Tayyip Erdogan's comments about Andrew Brunson (pictured above with his wife, Norine) were made during a live interview with TV news channel NTV and later picked up by the Reuters news agency.
The vague statement came after Erdogan previously suggested the 50-year-old's fate was linked to that of a Muslim cleric Ankara wants to see extradited to Turkey.
Turkey blames Fethullah Gulen - who has been living in the US since 1999 - for a bloody attempted to overthrow the Government in July 2016. Gulen denies any involvement.
Erdogan has so far resisted pressure from the US President, dozens of American senators and the United Nations to free Brunson, who has been living in Turkey for more than 20 years.
NTV canlı yayınından... pic.twitter.com/LfczN8T0D6
— Recep Tayyip Erdoğan (@RT_Erdogan) April 21, 2018
The leader of Resurrection Church in Izmir faces up to 35 years in prison if found guilty or terrorism links and espionage-related charges.
Among the accusations are claims that Brunson has connections to the Fethullah Gulen - but supporters say he is simply a pawn in a political face-off. Others claim he has been targeted specifically for his Christian faith.
The married father-of-two, who comes from Black Mountain in North Carolina, denies any wrongdoing.
Stay up to date with the latest news stories from a Christian perspective. Sign up to our daily newsletter and receive more stories like this straight to your inbox every morning.