The International Pass and International Open Pass are two new international calling packages from T-Mobile.

They are available to all new and existing Flext customers and T-Mobile claims they offer the lowest calls to the USA of any mobile operator – just 4p per minute to both landlines and mobiles.

The International Pass offers three options: the USA and Canada Pass for £5 per month for 125 minutes; the European and Australasia Pass, which is £5 per month for 50 minutes (which equates to 10p per minute to mobiles and landlines); and finally the Caribbean Pass, which is £7.50 per month for 50 minutes.

For the International Open Pass - there are two different options.

The International Open Pass Light costs £2.50 per month, which means that international calls to both fixed lines and mobiles cost 20p per minute.

And then there is the International Open Pass Max, which is £5.00 per month, so international calls to landlines cost just 4p per minute, and calls to mobiles 15p per minute.

The call plans come in on 1 April.