If the Constitutional Court in Pristina decides that the Brussels agreement on the ZSO is contrary to the laws of Kosovo, it will not be implemented, said  Kosovo Prime Minister Isa Mustafa.

Mustafa told the Kohavision broadcaster that the agreement on the formation of the Community of Serb Municipalities (ZSO) "was signed only after he received assurances from the EU and the U.S. that it will not be possible to form a 'third authority in Kosovo'." "The points of agreement on the ZSO will be forwarded to the Constitutional Court who will decide. If the Constitutional Court says some of the points of the agreement are not in accordance with the Kosovo Constitution, we will not implement them, and if the entire agreement is declared unconstitutional, then we will not implement it," said Mustafa.

This will, he said, "be decided by the Constitutional Court - otherwise the agreement will be implemented because it is an international obligation."

Mustafa also said that his government "could declare the ZSO illegal if does not adhere to the laws and the rules" of the government in Pristina. "They (Serbs) can declare autonomy today but that would not be valid, because they are forced to respect the laws of Kosovo. Otherwise Kosovo's institutions will have to take measures. Those who violate the law can end up in jail and that is guaranteed by the agreement on the judiciary," said he.

After weeks of blockade of the Kosovo parliament by three opposition parties that are against the agreement, Kosovo President Atifete Jahjaga, in agreement with parliamentary parties, forwarded the document to the Constitutional Court. The radical opposition Self-Determination party said they will not recognize the decision of the court, either, and will continue to block the assembly.

This development - which came a day after Pristina signed the Stabilization and Association Agreement with the EU - is considered by Serbia to be an act of obstruction of the implementation of the Brussels agreement.

Prime Minister Aleksandar Vucic said in Moscow after his talks with Russian President Vladimir Putin that Serbia will provide "a serious response" over Pristina's moves.