Costanza de Toma is an Italian national, but has lived in the UK for 22 years. She works with a pressure group, the3million, to try to represent the interests of citizens affected by Brexit.
At least 400 individuals, including the super-rich from Russia and Ukraine, have allegedly received Cypriot citizenship by investing in the country
Several European countries do not allow dual citizenship for citizens who apply for a British passport ahead of Brexit.
Larissa Waters, who made the headlines for breastfeeding in the Australian parliament, has resigned after realising she is a dual national.
A record 2,865 British citizens were naturalised in Germany in 2016, up from just 622 the previous year.