Ukrainian President Petro Poroshenko (2nd L) speaks during a meeting with U.S. Secretary of Defense James Mattis (not in the picture) at the Pentagon in Washington D.C., the United States, on June 20, 2017. (Xinhua/Ting Shen)

KIEV, Dec. 18 (Xinhua) -- The possible suspension of aid from the International Monetary Fund (IMF) is a main threat to Ukraine's financial stability in the coming years, the country's central bank said in a report on Monday.

"Without support from international institutions, a successful roll-over of the more than 20 billion U.S. dollars of sovereign and state-guaranteed debt maturing in 2018-2020 is unlikely," the National Bank of Ukraine (NBU) said in its biannual Financial Stability Report.

To maintain its economy afloat, Ukraine should start negotiations with the IMF to launch a new cooperation program before the current one expires, the report said.

Among other risks to financial stability, the NBU listed slow pace of structural economic reforms, low efficiency of state-owned banks, and its weak legal system.

Under the cooperation program launched in 2015, the East European country has got about 8.7 billion dollars from the global lender, which helped its economy avoid collapse amid the crisis.

Ukraine is counting on receiving an additional 3.5 billion dollars from the IMF before the program expires in 2019.

To continue the aid, the global lender requires Kiev to deepen economic reforms and enhance its fight against corruption.