ISLAMABAD -- The Pakistani Taliban said Thursday they have indefinitely extended a ceasefire with the government in Islamabad, following two days of talks with a delegation of Pakistani tribal elders that were hosted by the Afghan Taliban.

According to Mohammad Khurasani, a spokesman for the outlawed Tehrik-e-Taliban Pakistan group or TTP, the decision was made after "substantial progress" in the talks with the 50-member team of elders.

He did not elaborate and there was no immediate confirmation from the Pakistani government about the extension of the truce.

The Pakistani Taliban are a separate group but allied with the Afghan Taliban, who seized power in their country last August as the U.S. and NATO troops were in the final stages of their pullout from Afghanistan.

The TTP has waged an insurgency in Pakistan over the past 14 years, fighting for stricter enforcement of Islamic laws in the country, the release of their members who are in government custody and a reduction of Pakistani military presence in the country's former tribal regions.

Khurasani, the TTP spokesman, said the talks in Kabul would continue in the coming days. There was no statement from the Afghan Taliban, who in the past have only said they offer neutral ground for the talks.

The Taliban in Afghanistan have also been encouraging the new government in Pakistan to reach a peace agreement with the Pakistani Taliban. The previous truce between the two sides expired on May 30. So far, none of the ceasefires have paved the way for more permanent peace.

The Pakistani Taliban have for years used Afghanistan's rugged border regions for hideouts and for staging cross-border attacks into Pakistan and have now been emboldened by the return to power of the Afghan Taliban.

The group wants Pakistani government forces pull out of former tribal regions of the northwestern Khyber Pakhtunkhwa province, release all the TTP fighters in government custody and revoke all the legal cases against them.

The government in Islamabad, on the other hand, wants the Pakistani Taliban disbanded and for the insurgents to accept Pakistan's constitution and sever all their ties with the Islamic State group, another Sunni militant group with a regional affiliate that is active in both Afghanistan and Pakistan.

The Pakistani tribal elders were sent to Kabul as intermediaries because under Pakistan's constitution, the government cannot negotiate -- at least not directly -- with those waging an insurgency against it.