Solana gave an interview with the Montenegrin news agency Mina on Sunday adding that Brussels also had a role in that process.
Explaining his recent statement that the Montenegrin law on holding referendums should be amended, Solana said that separation from a state was a decision of the highest importance, which might cause rifts and which should be carefully made.
It is necessary to prepare all conditions, including the request for the exist from a state union, the required number of votes, who has the right to take part in the referendum and how the referendum question would be defined, the EU official said.
He added that the Constitutional Charter of Serbia-Montenegro offered a possibility for the cessation of the state union provided that the law on the referendum incorporated international standards.