The UK State Pension is payable worldwide and is uprated abroad where there is a legal requirement to do so. In some countries, however, there is no agreement with the UK for securing the social security rights of people moving between the two countries. As a result, pensioners who move to these countries still receive the State Pension but do not have their payments uprated as they would be for UK residents. The Department for Work and Pensions endeavours to make this clear to those thinking of moving abroad and publishes guidance on its website.
It has been and remains the policy of successive governments not to enter into new agreements with countries or territories where this would include up-rating pensions in order to contain the long-term cost of the UK social security system. I can tell you that this issue has been examined extensively by the domestic courts, culminating in a ruling by the European Court of Human Rights in 2010. In all these cases the courts have found in favour of the Government.