Spokesman Aimal Faizi says Pakistan has agreed to accept the delegation, including officials from Kabul's defense and interior ministries and its intelligence service.
The team could leave for Islamabad as soon as November 22.
Rabbani's assassination at his Kabul home in September by a turban bomber has stalled efforts to talk peace with the Taliban in Afghanistan.
Afghan officials say the killing was planned in Pakistan and carried out by a Pakistani suicide bomber.
Pakistan initially refused to cooperate in the probe. But Islamabad agreed to accept the Kabul delegation after pressure from Afghan and Turkish officials at a conference in Istanbul earlier this month.
compiled from agency reports