UK energy firms have been forcing clients to install prepaid meters while also overcharging the devices, which led to public outrage and prompted the government's Regulator Ofgem to interfere and crack down on the forced installations, AFP reported on Tuesday.

The energy providers also have the power to cut off supplies to customers, making it difficult for citizens not to comply with their terms.

Reports earlier this year claimed that British Gas contractors sent debt collectors to break into clients' homes and forcefully install prepayment meters (PPMS).

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Ofgem introduced a regulation, which was approved by all energy suppliers, that prohibits forced installations for citizens with health issues or those who are over 85 years of age.

But the decision was not received well by pressure groups, who accused the body of not doing enough and slammed the regulator for not halting forced PPMs altogether.     

"If and when involuntary PPMs are used, it must be as a last resort," said Ofgem CEO Jonathan Brearley on Tuesday.

"Customers in vulnerable situations will be given the extra care and consideration they deserve, over and above the rules already in place, by suppliers -- something that has clearly not always been happening."

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