Phone operator T-Mobile will next month increase its charges for customers making calls in Europe — just as EU rules capping rates come into effect.

From July, operators have to cap the cost of texts to a maximum 11p, while calls made to Britain will be limited to 38p a minute.

However, the caps exclude Vat, now at 15%. T-Mobile, which already charges 38p a minute, will use the loophole to increase rates to 43p. All other operators charge a maximum of 38p for contract customers.

It will be the first time T-Mobile has increased prices since 2007, when it cut rates from 55p a minute. Its text rate will, however, fall from 25p to 11p, prompting some analysts to suggest that higher call charges are a way of recouping lost revenue.

T-Mobile blames the weakness of sterling for the increase, even though the pound has rallied recently.

O2 and T-Mobile also charge customers travelling abroad for messages left on voicemail. T-Mobile charges monthly contract customers 63p a minute, while pay-as-you-go users are charged 44p. O2 charges 35p a minute, Vodafone and Orange charge only if the voicemail message is retrieved.