Turkish Prime Minister Ahmet Davutoglu on Monday rejected holding talks with Turkey's main pro-Kurdish party over a new constitution because of the "disrespectful" attitude of its leadership.
The premier's blackballing of the Kurdish Peoples' Democracy Party (HDP) from discussions comes as the army wages a relentless campaign against Kurdish militants in the southeast.
"It is not appropriate to accept them (the HDP) as negotiators after their disrespectful and provocative comments," Davutoglu said at a news conference before travelling to Serbia.
Davutoglu will launch negotiations with parties this week on a new charter after the ruling Justice and Development Party (AKP) co-founded by President Recep Tayyip Erdogan regained its majority in November 1 elections.
Davutoglu on Saturday cancelled a planned meeting with the HDP, accusing its co-chair Selahattin Demirtas of benefiting from the renewed violence and of polarising the country.
Demirtas was accused by the premier of "treason" a high-profile visit to Moscow just a month after Turkey's shooting down of a Russian warplane led to a crisis in ties.
"I can discuss the constitution with anyone, but the unity of Turkey is not a matter of discussion," Davutoglu said.
On Sunday, the Democratic Society Congress (DTK), an association of Kurdish political organisations, released a declaration calling for self-rule in the country's southeast.
"The rightful resistance waged by our people against the policies that undermine the Kurdish problem, is essentially a demand and struggle for local self-governance and local democracy," the 14-article declaration said.
Turkish security forces are currently imposing curfews several towns in the Kurdish-dominated southeast of Turkey in a bid to root out Kurdistan Workers' Party (PKK) rebels from urban centres.
The operations mark a new escalation in the over three decade conflict with the PKK after a fragile truce collapsed in July after just two-and-a-half years.
The army said on Saturday nearly 200 PKK militants were killed in the operations since the offensive began in mid-December.
The strongman of Turkish politics for more than a decade, Erdogan has long been pushing for a new constitution to transform his post into a powerful US-style executive presidency.
However the AKP still does not command the two-thirds or three-fifths majority needed to change the constitution without support from other parties or a popular referendum, respectively.
The government accuses the HDP of being the political wing of the PKK, although the party vehemently rejects the label.