The idea of holding a referendum came after Eurosceptics have gained popularity in the country, especially with regard to the demand from Brussels to pay an extra £1.7bn and a rising influx of migrants, which the UK government is unable to control.
"The referendum must take place before the end of 2017. If I think we could do that earlier I would be delighted. The sooner I can deliver on this commitment of a renegotiation and a referendum… the better," Cameron told BBC correspondent.
Late November, UK Prime Minister David Cameron made a public statement, saying that the government is planning to restrict the influx of immigrants by decreasing the attractiveness of the UK's domestic welfare system and depriving newcomers of social and healthcare benefits. According to the new initiative, immigrants will have to work for four years before they get any social advantages.
The measure is designed to strengthen control over the migration process. However, it has been sharply criticized by German Chancellor Angela Merkel who opposes the restrictive initiatives of that kind and says she will not allow the EU's rules on freedom of movement for workers to be abandoned, according to Reuters.