The move raised the prospect of fresh tensions between Ankara and the Kurds in the wake of already renewed violence and bloodshed that marred the run-up to the June 12 elections, threatening to re-ignite a conflict that has already claimed some 45,000 lives.

A spokesman for the lawmakers slammed the ruling to strip jailed Kurdish politician Hatip Dicle of his seat as "the last straw" in "operations and obstructions" targeting efforts for a peaceful end to the Kurdish conflict.

"We will not go to parliament until the government and the parliament take a concrete step to remedy this injustice and provide opportunities for a settlement by opening the way for democratic politics," Serafettin Elci, one of the lawmakers, told reporters.

He spoke after an emergency meeting that the deputies and officials of the Kurdish Peace and Democracy Party (BDP), which is backing them, held in Diyarbakir, the largest city of the Kurdish-majority southeast.

Elci urged the ruling Justice and Development Party, which took over Dicle's seat, to "immediately return the stolen seat to its owner."

The new parliament is to convene Tuesday for an oath-taking ceremony.

BDP-backed candidates won 36 of the 550 parliamentary seats in the elections, a record number for Kurdish nationalists.

The BDP fielded them as independents to get around a 10-percent national threshold that parties are required to pass to enter parliament.

However the Higher Electoral Board ruled late Tuesday that Dicle, 57, was not eligible to run in the elections because of a 20-month jail sentence on terror-related charges.

Dicle, in prison since 2010 awaiting trial in a separate case, had been expected to be freed to assume his seat.

The legal jumble arose from the fact that Dicle's sentence was upheld just four days before the polls, when the list of candidates had been confirmed.

His was convicted for a speech deemed "propaganda for an armed terrorist organisation" -- a reference to the outlawed Kurdistan Workers Party (PKK), which has led a bloody separatist insurgency in the southeast since 1984.

Five other Kurds who were elected on the BDP-backed list remain in prison, awaiting trial on charges of collaborating with the PKK.

Their lawyers have initiated legal procedures to secure their release in line with a precedent dating back to 2007 when a Kurdish activist awaiting trial in jail was freed after she won a parliamentary seat.

Piling up pressure on Ankara, the PKK last week put forward tough conditions for the extension of a unilateral truce it declared last August.

Eager to boost its EU bid, Turkey has notably broadened Kurdish freedoms in recent years: they can now broadcast in Kurdish, teach their mother tongue in private courses and use it in political life.

The Kurds, however, have upped the stakes, demanding constitutional recognition and autonomy.