What is the cheapest way to dial a portugal Mobile from a UK landline.

Thank you.

or via 0871 754 3939 @ 6p/min

or via 0871 343 9292 @ 9p/min

or via 0871 999 7676 @ 10p/min

none of the above require the setting up of an account

Not a PSTN solution but if you have access to a PC and broadband and if you or a Portuguese friend can set this up ...

http://www.vodafone.pt/main/Servicos+Roaming/Servicos/Vodafone+web+phone

You will effectively have a PC based Portuguese 'web phone' with a Portuguese number, that you can use in the UK or anywhere else.  If you choose the right PAYG tarrif you should be able to achieve best possible savings. ('VitaminaP' rates are approximately as follows - first minute about 15 eurocents thereafter 5 eurocents per minute)  If you make calls longer than one minute then you start to save, the other benefit being that you can also receive inbound from Portuguese contacts and they get charged at their local rate).  I must admit I haven't tried it yet and would be interested to know if you can make it work !