Taliban Pakistan and Tehreek-e-Taliban Pakistan (TTP) have agreed on a one-month ceasefire which may be extended if both sides agree, a spokesmen said on Monday, opening the possibility of a fuller peace accord to help end years of bloodshed.

The Pakistani Taliban are a separate movement from the Islamic Emirate of Afghanistan (IEA) and have fought for years to overthrow the government in Islamabad and rule the South Asian nation of 220 million, Reuters reported.

There have been numerous failed attempts to reach peace agreements in the past. The latest talks were opened following the victory of the IEA leaders in August and the two sides have been meeting across the border in Afghanistan, with the aid of IEA leaders.

“The government of Pakistan and banned Tehreek-e-Taliban Pakistan have agreed on a complete ceasefire,” Pakistan’s Information Minister Fawad Chaudhry said in a statement, adding that the ceasefire would be extended as the talks progressed.

Best known in the West for attempting to kill Malala Yousafzai, the schoolgirl who went on to win the Nobel Prize for her work promoting girls’ education, the TTP has killed thousands of military personnel and civilians over the years in bombings and suicide attacks.

Among its attacks was a 2014 assault on a military-run school in Peshawar, near the border with Afghanistan, which killed 149 people including 132 children.

As recently as Saturday, it claimed a bomb blast that killed four soldiers and wounded another in North Waziristan tribal district. It said the attack was in revenge for the killing of four of its fighters two days earlier.

Chaudhry said the ceasefire agreement would be under the Constitution of Pakistan and would ensure state sovereignty and national integrity.

The TTP, which sources said had been demanding the release of a number of prisoners as a condition for full ceasefire negotiations, said it was “ready for a dialogue that will lead to lasting peace in the country”.

It said the ceasefire would come into force from Tuesday and last until December 9 and could be extended if both sides agreed. Special committees had been set up to try to map out the negotiation process, Reuters reported.

The agreement comes days after the government in Islamabad reached an accord with another militant group Tehrik-e-Labaik Pakistan or TLP, after weeks of violent clashes.