Speaking on Nova TV's primetime news, he said there had been tensions in the past between the HDZ and the SDSS, one of its ruling coalition partners, but added that a solution had always been found.

"Until (elections on) December 4, we will do our job regarding what we have in parliament, what the government has to do, but also regarding what we as a party have to do, and if we disagree on something, and we don't agree with (the bill), we will clearly say so," said Pupovac.

The bill, recently sent by the government to parliament, would declare null and void the legal acts and decisions of the now defunct JNA, the former Yugoslav federation and the Republic of Serbia relating to the 1991-95 war in Croatia.

Asked if he had known before about indictments against 44 Croatian citizens issued by the JNA prosecution, Pupovac said he had not, but added that this was not something new and that the process of Croatian-Serbian cooperation, notably regarding delicate matters such as backlog war crimes cases, had begun long before that.

Pupovac said those attacking the 2006 agreement between the two countries were forgetting that based on it, the Serbian judiciary had taken over many cases, held trials and handed down verdicts, since the agreement enabled the Croatian judiciary and state prosecutor to submit the necessary documentation for holding proceedings in Serbia.

"Just as Croatia would not like someone else to determine its laws, the same should apply to other countries, notably in such delicate matters as war crimes, which is a matter of international law and international commitments," he said.

"It is only necessary to agree on the how, not on the whether or not. There is no doubt that this bill will complicate cooperation in the region and that, if passed in parliament, it will complicate Croatia's relations with the Hague (war crimes) tribunal, Brussels and the European Union, and notably relations on the political scene," Pupovac said.