Speaking to the press, Grbin regretted that the party had not stated earlier that it objected to the draft of the amendments.
He said he had talked with the HDSSB, asking them to talk and see what they would do.
Given that the HDSSB's withdrawal means that parliament will not have the 101 votes required to pass the amendments, Grbin said it was evident that they would not be discussed at a parliamentary session later this week.
The Constitution committee will not discuss them either and the ruling coalition will take them off the agenda of this week's parliamentary session.
Grbin would not speculate when the Constitution might be amended, announcing further talks on the matter.
Asked how failure to adopt the amendments by January 1 would reflect on a decision to extradite former Yugoslav secret agent Josip Perkovic to Germany, where he is wanted for the 1983 murder of a Croatian dissident, Grbin said this had nothing to do with Perkovic's extradition.
The constitutional amendments envisage lifting the statute of limitations on all first degree murders. Unless they are adopted by January 1, when the European Arrest Warrant will be applied also to crimes committed before August 2002, a court will decide if the statute of limitations has expired in Perkovic's case and, if it finds that it has, refuse his extradition.