Ukraine is able to export electricity for the first time in six months as its energy infrastructure recovers from months of repeated Russian attacks.
Russia began its lengthy and deliberate assault on Ukraine's energy infrastructure last October.
It led to power cuts and scheduled blackouts, leaving towns and cities in darkness during winter.
Ukraine was forced to stop electricity exports - but will now be able to sell its excess power again.
Energy Minister Herman Halushchenko signed an executive order authorising the exports, although local customers remain the priority.
He said the system had been producing extra capacity for almost two months and that Ukrainians were not facing restrictions.
"The most difficult winter has passed," Mr Halushchenko said on Friday.
"The next step is to start exporting electricity, which will allow us to attract additional financial resources for the necessary reconstruction of the destroyed and damaged energy infrastructure."
He also praised the "titanic work" of engineers and international partners to restore the system.