Portugal has tightened a law that grants citizenship to descendants of Sephardic Jews and which allowed Russian oligarch Roman Abramovich to become a citizen, but the changes will not be retroactive, the foreign minister said on Wednesday.

Portugal has tightened a law that grants citizenship to descendants of Sephardic Jews and which allowed Russian oligarch Roman Abramovich to become a citizen, but the changes will not be retroactive, the foreign minister said on Wednesday.