The arrest in France of Kosovo's former prime minister Ramush Haradinaj on suspicion of war crimes threatens to derail fragile negotiations between Serbia and Kosovo and ramp up tensions between the former foes.

Serbia wants to try the former leader of the insurgent Kosovo Liberation Army (KLA) for alleged atrocities committed against civilians during the 1998-1999 conflict against Belgrade forces.

After the conflict, which killed 13,000 people, the predominantly ethnic Albanian province of Kosovo became a United Nations protectorate and declared independence a decade later -- a move that has never been recognised by Belgrade.

The Serbian justice ministry on Tuesday requested the extradition of the former guerrilla fighter Haradinaj following his arrest by French police on January 4 at the eastern Basel-Mulhouse-Freiburg airport, under an international arrest warrant.

On Thursday, a French court will consider a request for the 48-year-old's release on bail.

For his compatriots, Haradinaj is a hero for his efforts to win independence from late Serbian strongman Slobodan Milosevic, and he is known as "Rambo" at home for his stocky build and military prowess.

"Haradinaj is Kosovo" read the placards of hundreds of war veterans who rallied against his arrest in front of the French embassy in Pristina last week.

Protesters gathered again on Wednesday, despite subzero temperatures, in several towns across Kosovo and in neighbouring countries with significant ethnic Albanian populations.

- Slow progress -

Haradinaj has twice before been acquitted of war crimes by the International Criminal Tribunal for the former Yugoslavia (ICTY) in The Hague.

He was elected premier in 2004 but resigned after 100 days in power to surrender to the United Nations judges.

Since his acquittal he has become a political opponent to powerful President Hashim Thaci and a resolute opponent of a historic 2013 agreement, brokered by the European Union, to normalise relations between Pristina and Belgrade.

The fragile talks have made progress in terms of the movement of people and goods, but it has never had great popular support, having been imposed by political leaders under pressure from the EU, which both sides aspire to join.

The dialogue advances laboriously, as illustrated by Kosovo's reluctance to set up an association of municipalities for its ethnic Serb minority -- around 100,000 people out of a population of 1.8 million.

In October, with the support of Belgrade, ethnic Serb MPs boycotted both the government and parliament to protest against the nationalisation of the Trepca mine, whose ownership is disputed, in tense northern Kosovo.

In a parliamentary session over the Haradinaj affair on Tuesday, Kosovo's opposition called for the suspension of all negotiations with Serbia "until all arrest warrants are waived against leaders or members" of the KLA.

- 'Block imports' -

"Serbia is working openly and on a daily basis to destroy the state of Kosovo. The government should immediately block imports from Serbia," said Ismajl Kurteshi, an MP with the opposition Vetevendosje (Self-Determination) party.

The group's methods to protest against the Serb association of municipalities -- which they fear will increase the influence of Belgrade -- have included repeatedly releasing tear gas in parliament.

Kosovo's Prime Minister Isa Mustafa said arrest warrants such as Haradinaj's were "completely illegal and unjust" with the consequence of "provoking tensions and conflicts, and damaging the European (integration) process in the region".

For its part, Serbia considers Kosovo the cradle of its identity in religion and affirms its guardianship its constitution. To think otherwise is politically taboo in Belgrade.

"Serbia will not give up on prosecuting Haradinaj or anybody else who has committed crimes against Serbs. The Serb people like all others deserve justice," Foreign Minister Ivica Dacic warned.

He said he had information about plotting among the Albanian diaspora to occupy Serbian diplomatic premises by force in Europe and the United States. Pristina has denied this.

The Haradinaj case comes as an international court is being set up at The Hague to try Kosovo rebels for war crimes.

There is speculation over whether President Thaci himself could appear, after a 2011 Council of Europe report accused him of heading a mafia-style network involved in assassinations, unlawful detentions and even trafficking captives' organs.

He strongly denies the charges.

(Source: AFP)