Every time planned electrical outages are imposed on his village in southern Moldova, 73-year-old retiree Vasili Donici passes the time by solving crosswords and puzzles in a room he illuminates using a small gas lamp.

More than 51,000 households were left without gas and 1,500 apartment buildings had no winter heat in Moldova's Moscow-backed separatist enclave, authorities said on Monday, as Moldova and Russia traded blame for an escalating energy crisis.

Moldova has accused Russia of triggering an energy crisis after tens of thousands of homes in its eastern breakaway region of Transnistria were left without heating, gas or electricity following the end of a Ukraine gas transit agreement last week.