In a joint statement, the two utilities said Hera would have 52% of the joint venture, EstEnergy, valued at 864.5 million euros (£773.1 million) and with core earnings of 69 million euros.

The deal, when completed, will also see Ascopiave buy gas distribution assets from Hera to make it the north-east's biggest gas distributor.

Ascopiave has been looking to sell a majority stake of its retail portfolio to focus on distribution. It attracted interest from players including Eni, Edison and Italian regional utilities A2A and Iren.

Italy's retail gas and electricity market is due to be fully liberalised in July 2020 and energy companies are vying for market share ahead of that date.

The deal, which will create the north-east's biggest retail energy company with more than 1 million clients, will be completed by July 31, the two utilities said.

Under the agreement Hera, Italy's biggest regional utility, will become the country's No 3 gas and power seller with more than 3 million energy clients.

(Reporting by Stephen Jewkes, editing by Giulio Piovaccari; Editing by Toby Chopra)