Providers of internet telephony must now allow emergency 999 calls over their networks or face the risk of enforcement action, regulator Ofcom has said.

The ruling follows a consultation in December last year after Ofcom research found that just over three-quarters of internet telephony users who cannot access emergency numbers, thought they could, or were unsure.

Ofcom said this could be dangerous in an emergency as people could waste vital time trying to make calls via online services before realising they were unable to.

The new rule known as General Condition 4 of the General Conditions of Entitlement for Voice over Internet Protocol (VoIP) providers came into force last week.

It means that operators such as BT, Vonage and Skype that offer services that connect VoIP calls to the public telephone network must now enable people to make calls to 999 and European emergency number 112.

It also states that the network operator must provide Caller Location Information for calls to the emergency call numbers.

Ofcom said that those providers unable to offer this could be fined up to 10 per cent of their annual turnover. However, this would be a “last resort”.

A representative for the regulator said: “We will work with providers first to address their needs and help them put these rules into place.”

However, it seems that Vonage is already one step ahead. Vincent Potier, managing director at Vonage UK said the company already did both these things and “always have done”.

“We are not the same as other VoIP providers. Vonage has worked actively with Ofcom on the Ofcom working groups leading up to these new 999 regulations,” he said.

We had not received a comment from Skype at the time of publication.