Energy supplier Panda Power is leaving the Irish market in the face of soaring wholesale gas and electricity prices.
The supplier has around 50,000 electricity customers and 10,000 gas customers in the Republic.
Panda is the largest Irish-based energy supplier to collapse as a result of the current crisis.
The firm is now the fourth supplier to exit the Irish market in the space of a few months following Iberdrola, Glowpower and Bright Energy.
The news comes at a time of huge volatility on energy markets, with gas and electricity prices close to record highs.
The energy regulator's "supplier of last resort" process will now kick in with all electricity customers of Panda moved to Electric Ireland and gas customers moved to Bord Gáis Energy.