The acting leader of the militant Kurdistan Workers Party (PKK) has threatened to launch a renewed offensive against Turkish forces, amid rising tensions between Turkey and Kurds in Turkish- and Syrian-occupied Kurdistan.

From a fortified location in northern Iraq's autonomous Kurdish region, Cemil Bayik, who took control of the PKK following the imprisonment of its leader, Abdullah Ocalan, cited the stalled peace process between the PKK and the Turkish government, as well as Turkish backing for Islamist rebels fighting Kurdish forces in northern Syria, as potential pretexts to rekindle hostilities with Ankara.

Talks between the two sides centered around Kurdish rights in Turkish-occupied Kurdistan, and came on the back of a 30-year conflict which left more than 40,000 dead and caused Turkey, the US and the EU to place the PKK on their list of banned terrorist groups.

But Kurdish activists have accused the Turkish government of Recep Tayyip Erdogan of simply using the talks as a way to buy time and consolidate Turkish control over Kurdish areas, saying Turkey has failed to deliver on most of its key promises.

"The process has come to an end," Bayik said in an interview with Reuters on Saturday. "Either they accept deep and meaningful negotiations with the Kurdish movement, or there will be a civil war in Turkey".

"Now we are preparing ourselves to send the withdrawn groups back to North Kurdistan if the government does not accept our conditions," he continued, warning that the direction of the process would become clearer "in the coming days".

He demanded that Turkey improve the conditions in which imprisoned PKK leader Ocalan is being held, and that the Turkish government deal with him on equal terms. Other key Kurdish demands include amendments to the constitution and the enlistment of a third party to oversee any further steps in the peace process.

Another issue which has fanned resentment among Kurds is the Turkish government's alleged support for Islamist rebel groups in Syria, who have been fighting a PKK affiliate - the Kurdish People's Protection Unit or YPG - and who have been implicated in numerous war crimes against Kurdish civilians in northern Syria, known by Kurds as Rojova.

The Turkish government denies supporting attacks on Syria's Kurdish population, and has even held talks with the YPG's leader, Salih Muslim, in Turkey. But those talks came to nothing, and Kurdish activists say it is an example of the same smokescreen strategy exhibited by Erdogan vis-a-vis diplomacy with the PKK.

The Kurds are the largest indigenous Middle Eastern nation without a state. Their homeland, Kurdistan, is currently occupied by Turkey, Syria, Iran and Iraq, although Kurds in Iraq enjoy autonomy under the Kurdish Regional Government, and even have their own police force and armed forces. All four countries have seen Kurdish insurgencies, although since the outbreak of the Syrian civil war most Kurdish militant activity appears to be focused on maintaining autonomy in northern Kurdistan and fending off attacks by both regime and Arab rebel fighters.

Kurds in Syria make up around 10% of the population, and are concentrated largely in the north of the country.

The possibility of a spillover of the Syrian conflict into Turkey has long been a concern of its government, and has been cited as one of the reasons for its alleged support for anti-Kurdish rebels there. The threat of another autonomous Kurdish region on its borders is seen as a security threat.

However, Bayik's threat may suggest that such a decision could backfire, as an emboldened Kurdish militant movement mulls its response to continued antagonism by Turkey.

It also underlines how the ongoing bloodshed in Syria is a destablising factor for the region as a whole, coming amid looming threats of an escalated spillover into Lebanon, should an upcoming Syrian military operation near its border go ahead.

Escalated violence in Iraq has also been partially attributed to continued instability in neighboring Syria, which has helped reinvigorate the presence of Al Qaeda in the region.