In fact, the vast majority of states worldwide allow only their own citizens to vote in national elections. Due to historical and political reasons, however, there are a few exceptions to the rule. In the United Kingdom, for instance, Irish citizens and Commonwealth citizens (with an indefinite leave to remain in the UK) are eligible to register to vote if they reside on the territory of the UK. In return, British citizens permanently residing in the Ireland (or in some Commonwealth states in the Caribbean) are eligible to vote in parliamentary elections, there. Only in a few countries outside Europe are non-citizens generally allowed to vote after a certain number of years of permanent residency, ranging from one year in New Zealand to 15 years in Uruguay. In Luxembourg, a proposal to grant the right to vote in national elections to non-citizens who have been permanent residents for more than 10 years was rejected in a referendum in 2015.