Kurdish politicians and activists have been aggressively promoting official use of Kurdish in recent months as part of their growing demands for regional autonomy â€" a goal shared by rebels whose fight has killed tens of thousands of people so far.
The pro-Kurdish Peace and Democracy Party, buoyed by steps taken by the government in expanding the use of Kurdish, including radio and television broadcasts and letting politicians campaign in the language, insist on regional autonomy, which has fueled nationalist sentiment and tensions that threaten to derail efforts to end the armed conflict.
The country's National Security Council responded bluntly after a meeting Wednesday night, saying the country was indivisible and that no attempt at challenging the official Turkish language will be accepted.
"We cannot allow any attempt to deny that the official language of the Turkish Republic, which symbolizes common grounds such as one flag, one nation and one land is Turkish," said the website of the presidential palace, citing the Council statement.
President Abdullah Gul's visit to Diyarbakir, the largest city in the southeast, was pre-planned. He has cautioned against exploiting the issue and urged Kurdish politicians to act more responsibly.
The pro-Kurdish party, however, issued a statement ahead of his visit to stress their demands once again.
"We hope the President's Diyarbakir visit will lead the way to education in the mother tongue and the use of Kurdish in public areas, and for our people to freely govern itself within the reality of Turkey," it said Wednesday.
The pro-Kurdish party has strong electoral support in the southeast and has been pushing for autonomy in the run up to general elections next summer. Several predecessors of the party have been shut down by Turkey's top court on charges of ties to the Kurdistan Workers' Party or PKK, a rebel group labeled as terrorist by the West and the current party is currently probed on similar grounds.
Private courses in Kurdish are available, but the language is not taught in schools. Turkey's constitution says the official language is Turkish and prosecutors are opening investigations into direct challenges to the law. In the eastern town of Erentepe in Mus province, Kurdish authorities have posted dual-language signs at the mayor's office.
Gul was also welcomed by posters in Turkish and Kurdish on Thursday, television reports said.
Osman Baydemir, the mayor of Diyarbakir, was expected to present a Turkish-Kurdish dictionary to the president in a scheduled meeting later Thursday, news reports said.
The Kurdish language debate heated up in November, during the trial of dozens of Kurds, including elected mayors, on charges of having links to the PKK. The court refused the suspects' demand to defend themselves in Kurdish, on grounds that the defendants were fluent in Turkish.
ANKARA, Turkey - Selcan Hacaoglu, The Associated Press
Associated Press reporter Erol Israfil in Istanbul contributed to this report.