The European Union's Justice Commissioner Vera Jourova has criticised the practice of selling "golden passports" to rich non-EU nationals, and urged the countries which do so to do more to ensure that citizenship isn't given to criminals.
Ms Jourova was quoted in the German daily Die Welt as saying that awarding citizenship can be a "serious security risk" because it confers rights including free movement within the 28 countries that make up the EU.
“Some countries must do more so that citizenship is not awarded to criminals who want to endanger Europe's security or engage in money-laundering," Ms Jourova said, but stopped short of pointing a finger at any particular countries.
She added that the EU's executive Commission will examine each member country's practices in granting citizenship to people from outside the bloc, and stated that a report on the issue had been brought forward from December to autumn.
The EU will then issue new, tougher guidelines calling for member countries to guarantee that candidates for citizenship won't damage the bloc, she added.
While Brussels argues that citizenship should be awarded only in cases where there is a genuine link to the country concerned, the decision to award citizenship is left up to individual countries.