An energy company responsible for about one quarter of Lebanon's electricity supply has turned off its generators, APA reports citing BBC.
Karpowership, a Turkish company, says it is owed more than $100m (£71m) by Lebanon and has not been paid in 18 months.
It also faces corruption charges, which it denies, and an ongoing legal fight.
Lebanon is in a major economic and political crisis, and already suffers regular power cuts, with many people relying on private generators.
The country has not had an agreed government in nine months, after the previous administration resigned in the wake of a devastating explosion at Beirut's port.
Hassan Diab is currently serving as caretaker PM. He stepped down after the blast in August but PM-elect Saad Hariri has so far struggled to form a government, leaving Mr Diab in the post until Mr Hariri can take office.