Milanovic "is aware that his government's performance is devastating, especially on the economic front," group vice president Gordan Jandrokovic told reporters.
He said Milanovic yesterday offended many MPs and representatives of some regions and that his treatment of HDZ (Croatian Democratic Union) deputy Davor Ivo Stier was especially insulting.
Asked why HDZ president Tomislav Karamarko had not commented on yesterday's Question Time, Jandrokovic said he would do so later.
He said Milanovic's announcement that a two-thirds parliamentary majority would be required to ratify a Croatian-Bosnian border agreement meant that the PM had given up on the ratification because he was aware that the HDZ and some other parties would not vote for it.
Jandrokovic accused Milanovic of being weak, insecure, uninformed and incompetent.
He accused the government of embarking on the ratification of the 1999 agreement with no strategy and unprepared. Asked if the HDZ would be responsible for the consequences if the deal was not ratified, he said Milanovic's Social Democrats and the ruling coalition would be responsible.