Baitullah Mehsud has an aversion to publicity and photographs
A top Taleban commander in Pakistan has ordered his followers to stop all attacks in the country.
Baitullah Mehsud is the man the Pakistani authorities say ordered the killing of Benazir Bhutto.
Pamphlets containing his order appeared in tribal areas along the Afghan border. Mehsud said anyone found violating the order would be punished.
Pakistan's new government has said it will deal with Islamic militancy through dialogue and development.
On Monday night the authorities set free Maulana Sufi Mohammad, the founder of an outlawed Islamist group that has fought in Pakistan and Afghanistan.
He was released under an agreement to renounce violence and help restore peace in the north-west valley of Swat.
The release has been welcomed by Pakistani Taleban.
Baitullah Mehsud's stronghold is in South Waziristan, an area that has seen many of the heaviest clashes between militants and the security forces in recent years.
"All members of Tehrik-e-Taleban (Movement of Taleban) are ordered by Baitullah Mehsud that a ban is imposed on provocative activities for the sake of peace," according to a leaflet distributed in the South Waziristan region.
Anyone who defied the order would be punished publicly, the leaflet read.
"No arguments will be accepted. It's a firm order," it said.
A spokesman for Baitullah Mehsud, Maulvi Omar, told Pakistan's Dawn News channel that the Taleban had lately been in touch with the new government in connection with a possible new peace deal.
He said Maulana Sufi Mohammad's release was part of that deal.
The BBC's Barbara Plett in Islamabad says reports now suggest that the authorities are close to a deal with Baitullah Mehsud's tribe.
The reports say the deal calls for an end to militancy, an exchange of prisoners, and an army withdrawal from the area.
It also requires the Mehsud tribes to expel foreign fighters from their territory.
American officials cautiously support the new government's efforts to reach peace through talks.
But they admit they are concerned and say there is a problem enforcing such agreements.
Our correspondent says that previous such deals have turned the tribal areas into a sanctuary for Taleban and al-Qaeda linked militants from where they have launched attacks on Nato troops in Afghanistan.
They also began hitting Pakistani targets when the army tried to stop them.
Taleban spokesman Maulvi Omar said Pakistani troops stationed in some areas of South Waziristan on Afghan border had already started withdrawing to pave the way for the peace deal.
Pakistan army spokesman, Maj-Gen Athar Abbas, however said "so far we have not received any orders from the government (to pull out the troops)".
Baitullah Mehsud is said to command about 20,000 pro-Taleban militants and a majority of them belong to the Mehsud tribe.
The previous government, that supported President Musharraf, said it had evidence from phone intercepts that Mehsud had organised the killing of former Prime Minister Benazir Bhutto in Rawalpindi in December.
He denies the charge.