Fitch downgraded Ukraine's long-term foreign currency Issuer Default Rating (IDR) to 'CCC' from 'B-', citing political instability in the country, Reuters reported.

Ukraine is struggling to prop up its currency amid a political crisis with anti-government demonstrators taking to the streets to protest against a move closer to Moscow's economic orbit. A debt crisis has left the country on the verge of bankruptcy.

"The financial system remains fragile, burdened by non-performing loans of 30 percent, and represents a contingent liability to the sovereign...," Fitch Ratings said.

Fitch said the falling reserves, a weak outlook for its currency and reducing prospects of Ukraine's access to external funding undermine its debt servicing ability.

Fitch ratings also cut the country's short-term foreign currency IDR to 'C' from 'B'.

Russia suspended a $15 billion bailout last week after President Viktor Yanukovich, in a concession to protesters, sacked the pro-Russian prime minister.

Ukraine's central bank on Thursday, Feb 6 introduced restrictions on certain types of foreign exchange purchase to help defend the stability of its banking system.

The hryvnia fell below 9 per dollar on Wednesday for the first time in five years. It traded at 8.53/8.56 against the dollar on Friday at 1430 GMT.