"Kalinic can file a complaint against this decision in the next three days," Kresimir Devcic, a spokesman for the court, said.
"If he does so, the final decision will be taken by the supreme court."
Djindjic was fatally wounded by a gunshot in Belgrade on March 12, 2003.
Last November, Serbia's top court rejected a final appeal and confirmed 40-year jail sentences for Milorad "Legija" Ulemek, the mastermind of Djindjic's assassination, and sniper Zvezdan Jovanovic.
Ten other suspects, including Kalinic, were given jail terms of up to 40 years for taking part in the attack.
The fight against organised crime and corruption is a major requirement from the European Union for any countries joining the bloc.
Croatia hopes to complete EU entry talks early next year, while Serbia applied for EU membership last year, but has not started accession talks yet.
Serbia and Croatia agreed to hand over suspects for investigations or trials, regardless of their citizenship, in an effort to boost the rule of law in the region.
If Kalinic is extradited, it would be the first such case covered by the June agreement.