An informed source at the Chiefs of Staff of the Iranian Armed Forces told that Turkey's army had launched an operation against the PKK along its eastern borders earlier in the day, adding that the Iranian Armed Forces have not been involved in the operation.
The source said: "The Armed Forces of the Islamic Republic of Iran will severely counter any group that intends to create insecurity in our country."
Turkish Interior Minister Suleyman Soylu said earlier on Monday that Turkey and Iran had carried out a joint operation against PKK militants.
"We started carrying out an operation with Iran against the PKK on our eastern border this morning (and) will announce the result," Turkey's news agency Anadolu quoted Soylu as saying.
Over the past few months, Turkish ground and air forces have been carrying out operations against PKK positions in the country as well as in northern Iraq and neighboring Syria.
In January 2018, Ankara launched a cross-border military operation inside Syria, code-named Operation Olive Branch, with the declared aim of eliminating the Syrian Kurdish militants of the People's Protection Units (YPG).
The YPG forms the backbone of the so-called Syrian Democratic Forces (SDF), an anti-Damascus alliance of predominantly Kurdish militants supported by the United States.
Ankara views the YPG as a terrorist organization and the Syrian branch of the PKK.
More than 40,000 people have been killed during the three-decade conflict between Turkey and the autonomy-seeking militant group.
Iran has had its own struggle with the PKK's Iranian offshoot, the so-called Kurdistan Free Life Party (PJAK), which has waged several terrorist attacks in western Iran over the past years.
The terror group carries out attacks in parts of Iran's West Azarbaijan province which borders Iraq, Turkey, and Armenia.