Moroccans continue to be the main recipients of EU citizenship, according to the data published on Monday.
It shows that in 2014, around 890,000 people acquired EU citizenship, down from 981,000 in 2013.
Since 2009, more than five million people in total were granted a citizenship of an EU member state. Of the total number of persons obtaining the citizenship of one of the 28 member states in 2014, 89 per cent were non-EU citizens.
The EU agency said that 125,600 - or 14 per cent of the total - of those who acquired EU citizenship in 2014 became citizens of the UK.
A Eurostat spokesman said the figures show that "overall, a rich diversity of recipients prevails in the EU."
However, the UK Independence Party, leading the Leave campaign ahead of Britain's In/Out referendum on 23 June, was quick to seize on the data to support its policies.
It has put the issue of immigration at the forefront of its campaign to quit the EU.
Its migration spokesperson Steven Woolfe, an MEP, said, "Every one of these 900,000 people granted EU citizenship membership now have an untrammelled right to come to live in the UK because of our EU membership. And this process will continue into the future unless we vote Leave on 23 June."
Woolfe added, "By voting to leave we will take back control of our immigration policy, half of which is completely under EU command. By doing this we can enhance our security and increase the wages of ordinary working people, many of whom have seen their wages depressed by an oversupply of cheap labour from Eastern Europe. On 23 June, we can take back control of our laws, our money and our borders. This sounds a great deal to me."
His comments come after Labour's shadow foreign secretary urged the Leave campaign to be more honest about necessity of immigration.
Hilary Benn said at the weekend that voters will be bitterly disappointed if they choose to leave the EU in the belief that it will significantly reduce immigration.
The senior MP said leaving the EU would not put a stop to high levels of immigration as foreign workers would be needed to care for Britain's ageing population and staff the NHS.
The clash over migration comes as a YouGov poll for the Sunday Times has Leave on 43 per cent and Remain on 42 per cent. The poll found that 41 per cent believe the Remain campaign has tried to frighten people, while 28 per cent believe the Leave campaign has.
A separate YouGov poll for the Adam Smith Institute has found that 54 per cent of people would support the UK pursuing a Norway-style relationship if it did leave the EU, though among those saying they would vote to leave, 45 per cent oppose it and only 37 per cent support it.
Eurostat, the EU's statistical agency that provided the new migration data, says that the largest group acquiring citizenship of a member state in 2014 was citizens of Morocco (92,700 persons, of which 88 per cent acquired citizenship of Spain, Italy or France).
Next were citizens of Albania (41,000, 96 per cent acquired citizenship of Greece or Italy) and Turkey (37,500, 60 per cent acquired German citizenship).
Moroccans, Albanians, Turks, Indians, Ecuadorians, Colombians and Pakistanis represented together a third (33 per cent) of the total number of persons who acquired EU citizenship in 2014, said Eurostat.
Romanians (24,300 persons) and Poles (16,100) were the two largest groups of EU citizens acquiring citizenship of another member state.
In 15 member states, at least nine out of every 10 who obtained citizenship in 2014 were non-EU citizens, said the Luxembourg-based agency.
At EU level, 89 per cent (or nearly 788,100 new citizens) of those granted citizenship were non-EU citizens, and 11 per cent (95,700) of another member state.
Almost one in every four persons who acquired an EU citizenship in 2014 became citizens of Spain (205,900 persons, or 23 per cent of all citizenships granted in the EU in 2014).
It was followed by Italy (129,900 or 15 per cent), the UK (125,600 or 14 per cent), Germany (110,600 or 12 per cent) and France (105, 600 or 12 per cent).