National and regional variations also occur within the BBC One and BBC Two schedules. England's BBC One output is split up into fifteen regions (such as South West and East), which exist mainly to produce local news programming, but also occasionally opt out of the network to show programmes of local importance (such as major local events). The other nations of the United Kingdom (Wales, Scotland and Northern Ireland) have been granted more autonomy from the English network; for example, programmes are mostly introduced by local announcers, rather than by those in London. BBC One and BBC Two schedules in the other UK nations can vary immensely from BBC One and BBC Two in England.