Customers shop at Athens Central Market in Athens, July 2, 2015. Greeks remain calm while the country entered uncharted territory since Athens failed to repay IMF as bailout run out on June 30, 2015. (Xinhua/Marios Lolos)

WASHINGTON, Sept. 23 (Xinhua) -- The International Monetary Fund said on Friday that Greece has made significant progress in unwinding its macro-economic imbalances, but growth remained elusive and risks are high.

"Recurrent political crises and confidence shocks associated with the inability to sustain the reform effort resulted in a high cost for society," said the IMF after concluding the 2016 Article IV mission.

The IMF expected the economic growth will remain weak and subject to high downside risks, and unemployment will likely stay in the double digits until the middle of the century.

The international lender urged Greece to continue to press reforms in key areas, including pension and taxation systems reforms, dealing with banking industry's bad loans, removing obstacles to investment and growth, in order to increase the economy's resilience.

Greece's debt continued to rise to unsustainable levels, despite debt relief from private and official creditors, said the IMF. It called for further debt relief to restore sustainability.