Related: Turkish FM: Cross-border Operation on PKK Not Invasion

Turkish Prime Minister Recep Tayyip Erdogan on Thursday denied media reports that his country has decided to close its air space to planes flying to and from northern Iraq, local media said.

Turkey has not decided to shut down any air space, Erdogan said, quoted by local broadcaster CNN Turk. But he failed to disclose more information.

Earlier in the day, local private NTV, citing an unnamed Turkish official, reported that Turkey has decided to close its air space to planes flying to and from northern Iraq as it stepped up efforts to fight the separatist Kurdish Workers' Party (PKK).

The decision was part of economic sanctions targeting groups supporting PKK militants operating in northern Iraq, the channel said.

NTV's reports and Erdogan's denial came one day after Turkey said it had taken all-round measures, including economic ones, to fight the PKK.

Turkish government spokesman and Deputy Prime Minister Cemil Cicek said Wednesday that Turkey will "fight against terrorism in all areas.

"In regard to the fight against terror, military, political, diplomatic and economic efforts are being made," Cicek made the statement after the weekly Council of Ministers meeting.

Turkey has now massed up to 100,000 troops along the mountainous border with Iraq in preparations for a cross-border operation to crush about 3,000-strong PKK rebels, which was approved by the parliament earlier this month.

The PKK, listed by the U.S. and Turkey as a terrorist group, took up arms against Turkey in 1984 with the aim of creating an ethnic homeland in the southeast. More than 30,000 people have been killed in the more than two decade conflict.