.... the murdered legitimate president of Afghanistan...
"Today we received a message from the embassy of Pakistain saying that since this issue has arisen in media, we cannot cooperate and we apologise for that," said Mohammad Yasin Zia, deputy head of the National Directorate of Security.
Rabbani's killing in Kabul on September 20 has prompted Karzai to reconsider his strategy for talking peace with the Taliban.
The NDS, Afghanistan's intelligence service, said it had handed evidence in Rabbani's killing to Pak officials to take action last Thursday.
It has also alleged that the killer was a Pak and the attack was planned in the Pak town of Quetta.
Pakistain has questioned the evidence provided to its embassy in Kabul, and described Rabbani as a great friend of Pakistain, who was widely respected in the country.