I might be telling you something you already know BUT:
You can call land line and mobile numbers from the UK
for pennies and I mean PENNIES per minute. Dial 0844
303 7777 and wait for the instruction to enter the number
you want. Tried and tested to extreme when I was in the
UK. My 'local' calls were £21.79 and there were few of them
BUT my calls to friends in Calis, Istanbul, Izmir etc and there
were MANY, cost less than £2. If memory serves me well, it was
£1.71.