The Community of Serb Municipalities, which represents Serbs in the north, made its threat at a protest in the northern town of Zubin Potok on Monday, held under the slogan “We are All the Same - Who is Next?”

"If the campaign against Serbs [in Kosovo] continues, the legally-elected parliamentarians, mayors, presidents of municipal assemblies and council members will consider their participation in all institutions in Kosovo and Metohija," the organisers said in a statement that was read out at the rally.

The rally came after Kosovo police last week tried to deliver subpoenas to the former and current municipal presidents of Zubin Potok, Slavisa Ristic and Stevan Vulovic.

Dragan Jablanovic, the mayor of Leposavic, said he believed that the goal of the arrests was to intimidate local Serbs.

"Such moves do not lead to the stabilization of the situation," Jablanovic said.

The Community of Serb Municipalities called upon the international community and the EU rule-of-law mission in Kosovo, EULEX, to immediately and unconditionally allow "all the unjustly indicted Serbs to be released pending trial".

Otherwise, it said, it would be forced to consider the possibility of terminating cooperation with EULEX.

EULEX has confirmed that there was an attempt to subpoena Vulovic and Ristic, but has not given any information about the reasons for it.

Ksenija Bozovic, the president of the municipal assembly of North Mitrovica, said that other detained Kosovo Serbs like politician Oliver Ivanovic should also be freed pending trial.

"There has been a lot of injustice; Kosovo police and EULEX should finally start working fairly and lawfully. We recall that the international community must be status-neutral and not in the service of the authorities in Pristina," Bozovic said.

In June, a pre-trial judge at the Mitrovica Basic Court extended Ivanovic’s detention on remand until August 26.

He was arrested in January on suspicion of involvement in war crimes and in violence in 2000 in which ten Kosovo Albanians were killed and many more wounded and driven from their homes.

At the time, he was a leading "Bridge Watcher", one of the hardline Serbs who patrolled the main bridge in Mitrovica dividing the town into Serbian and Albanian sectors.

Belgrade maintains that the arrest was politically motivated.