Moody's said that "year of pain" awaits the Turkish economy next year 2019, especially after the Turkish lira recorded its worst performance this year.
Moody's said that the fall in the pound this year will translate into serious economic problems such as slow growth in developed and emerging markets.
Moody's predicts that the Turkish economy will shrink in the first half of next year, as the price of pounds falls and the cost of credit rises.
"Inflation and the sharp rise in credit costs are expected to affect households' purchasing power, private consumption and investment," she said.
The IMF said growth in the Turkish economy could fall to 0.4 percent next year, from 3.5 percent this year.
"A weak pound and rising borrowing costs will be a reflection of investment and consumption," the IMF said.
Turkish prosecutors have ordered the arrest of 103 soldiers on suspicion of links with Fatah, which Ankara accuses of being behind the failed coup attempt in mid-2016, the Anatolia news agency reported.