Officials from Afghanistan, Pakistan, China and the United States are due to meet in Islamabad on Jan. 11 to try to revive a peace process that stalled in July when the news came out that Taliban leader Mullah Mohammad Omar had died two years earlier.
Prospects of success have been clouded by bloody infighting in the Taliban over the leadership succession which has made it difficult to identify which parts of the movement may be open to talks and which remain committed to the insurgency.
The legitimacy of Omar's former deputy Mullah Akhtar Mansour, who assumed the leadership in July, is rejected by some militants. Rivals who accuse him of being beholden to Pakistan are suspicious that he hid Omar's death for so long.
"It is obvious that there are groups of Taliban, not a unified movement," Ghani told a news conference on Thursday, Reuters reported.
"The fundamental issue here is the choice: choose peace or terrorism," he said. "There will be no tolerance for terrorism."
Next month's meeting will be followed by another encounter in Kabul, with Afghanistan initially represented by Deputy Foreign Minister Hekmat Khalil Karzai.
The United States and China have both been pressing hard for a resumption of talks with the Taliban but mutual suspicions between Kabul and Islamabad, as well as the factional fighting within the Taliban, have held up the process.
Afghanistan has long said Pakistan is harbouring Taliban leaders and sponsoring the insurgency as a means of exerting control over Kabul, a charge that Pakistan rejects, saying it too is a victim of terrorism.
For its part, the main faction of the Taliban has rejected peace talks as long as foreign troops in NATO's training and assistance mission remain in Afghanistan.
Despite its leadership disputes, the Taliban has inflicted heavy casualties on Afghan forcesthis year.
As well as the brief capture of the northern city of Kunduz in September, the insurgent movement has also threatened to take the volatile southern province of Helmand after overrunning several district centres