The zero-tariff on onions will remain in effect until Feb. 28.
The decree stated that the purpose of the move is to curb the rise in the price of onions and to keep the domestic market price of the vegetable at a reasonable level and to prevent any speculative price moves.
Turkey had imposed a 30.9 percent duty on onions imported from Singapore, while the corresponding customs duty rate imposed on other countries was 49.5 percent.
The price of onions had soared 184 percent in 2018 from the previous year. A kilogram of onions was sold at 4.18 Turkish liras ($ 0.8) in December 2018, the latest inflation data from the Turkish Statistical Institute (TÜİK) showed.
In December, the price of the onion increased by 16 percent compared to the previous month.
Last year food prices increased by 25 percent while the headline consumer price inflation stood at 20.3 percent. On a monthly basis, food prices were up 1.1 percent.
In its latest inflation report, published in October last year, the Central Bank said it had revised its food inflation forecast to 13 percent from 10 percent for end-2019.
Separate data from TÜİK showed that last year 1.93 million tons of onions were produced in Turkey, whereas the corresponding figure was 2.13 million tons for the previous year.
Overall vegetables output of the country declined by 2.6 percent last year from 2017 to 30 million tons.