Cheapest way to call UK phone numbers from Morocco?

Hi, I need to call Gatwick Airport as they have emailed me to say my car has been damaged by one of their drivers whilst it was being moved in one of their car parks at the airport and need to discuss repairs etc.

Does anyone what is the cheapest way to place an international call to UK from Morocco? Can I buy an international calling card from Morocco?

I use skype. Download it and purchase credit and call on skype

Thanks that seems simple and convenient, i will try that

Skype works. You have to set up a link to your bank account. That can be either a subscription or a single payment that auto-renews when your cred runs out.
You can cancel at any time.
Viver has 'Viber out'. Not tried that but I gather it works.

Hi, if you collected a sim card when entering Morocco at the airport they tend to have Zone 1(UK is part of Zone 1) Calling as part of the package (Inwi) . However if you have not if you have a local sim you can buy call times cheaply you can visit INIWI also

SKYPE as other people have mentioned is also good way to call the UK. So long as you have a good internet connection.