The ministry said in a statement that it was "against" international law to visit the region without receiving permission from the Azerbaijani authorities, which may impose "various sanctions" with regard to its national legislation.

Ankara added it was not "possible" to provide a consular protection for Turkish citizens who would travel to the occupied territories.

Four Turkish citizens traveled to the Nagorno-Karabakh region "illegaly" on Sept. 22 without the consent of related Azerbaijani authorities.

The office of Azerbaijan’s prosecutor general filed on Sept. 28 a criminal case against them for "illegally crossing Azerbaijan’s state borders".

Turkish Foreign Ministry spokesman Huseyin Muftuoglu said in a statement on Sept. 29 that the four Turkish citizens had traveled to the occupied territories "on their own initiatives, without consulting any official authority and [this] under no circumstances reflects Turkish official policy".

Muftuoglu said Turkey would continue to support Azerbaijan in its just cause.

"Turkey acts in close solidarity with its Azerbaijani brothers and sisters in regard to ending the occupation of one-fifth of the Azerbaijani territories which has lasted for over a quarter century," he added.

Azerbaijan and Armenia remain in dispute over the occupied Karabakh region.

Karabakh broke away from Azerbaijan in 1991 with Armenian military support, and a peace process has yet to be implemented.