LONDON, Nov 13 (Reuters) - British petrol station operator EG Group said on Monday it would buy Tesla (TSLA.O) ultra-fast charging units to boost its electric vehicle charging network across Europe, as the EV maker continues to expand the reach of its charging business.

EG, owned by the billionaire Issa brothers who also own UK supermarket chain Asda, will expand its charging network to more than 20,000 EV chargers at its own sites over time, from above 600 currently deployed.

The first Tesla chargers will be installed by the end of this year, EG said, though it didn't provide details on the cost or time frame for the total purchase.

The "open network" Tesla chargers will be accessible to all EV drivers regardless of their vehicles' brand.

"The rapid installation of reliable, easy-to-use EV charging infrastructure is the right step towards a sustainable future," said Rebecca Tinucci, Tesla's senior director of charging infrastructure.

EV adoption is seen as key to British and European climate goals, and the car industry has called for faster expansion of public charging networks to encourage drivers to make the switch.

Tesla said in February it would open part of its U.S. charging network to rivals' EVs as part of a $7.5 billion federal program to expand EV use and cut carbon emissions.

BP's (BP.L) EV charger unit said last month it was ordering $100 million worth of Tesla ultra-fast chargers for its U.S. network. Ford (F.N) also said last month it would add more of Tesla's superchargers to its EV charging network than previously forecast.

The UK had just over 49,000 public electric vehicle charging devices installed as of Oct. 1, according to government figures.

Reporting by Sachin Ravikumar; Editing by Kate Holton and Bernadette Baum

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