The convention, which the Council of Europe drew up in 1997, will affect Croats from Bosnia-Herzegovina and also Croats from other countries established after the break-up of the Socialist Federal Republic of Yugoslavia (SFRY).
So far, a majority of citizenship applications have been sent from the area in question.
According to figures released by the Interior Ministry, between 12-15 thousand requests are received annually from that category of applicants and a vast majority of them are granted Croatian citizenship.
Under the existent law, ethnic Croats can become Croatia's citizens irrelevant of the fact whether they have a residence in Croatia. On the other hand, members of other ethnic groups should meet also the residence requirement regulating their fixed abode in Croatia for at least five years.
This provision will be the greatest challenge to a task force set up to prepare amendments to the Croatian citizenship law in compliance with the convention which proscribes discrimination on any ground, including gender, religion, race, colour or national or ethnic origin.
The Council of Europe also has expressed some objections to the provision of the Croatian law which facilitated ethnic Croatians' bid to get Croatia's citizenship.
Assistant Interior Minister Zarko Katic has told Hina that this is one of the most challenging sections of the law.
According to Katic, almost all European countries stipulate easier requirements for their ethnic compatriots living in other countries than for other applicants seeking citizenship. However, all these requirements contain a condition defining the residence on their territory.
Katic has said that Croatia will also follow such solutions including permanent residence before five and ten years.