A government official confirmed the leaflets were genuine and were issued by Mehsud's group.
"It's a confidence-building measure, part of the peace process that has begun with local militants," the Reuters news agency reported a government official as saying.
Mehsud's Tehrik-e-Taliban is an umbrella organisation, formed last year, of various groups based in Pakistan's ethnic Pashtun border lands.
Pakistan's new coalition government, led by Bhutto's Pakistan People's Party, has started negotiations in a bid to break with the policies of Pervez Musharraf, the Pakistani president whose policies to tackle the armed groups ranged from military action to appeasement.
In recent years, Pakistani authorities have struck a number of pacts with groups in both South and North Waziristan but the deals, intended to stop attacks into Afghanistan, have so far been temporary.
But critics, including US commanders in Afghanistan, said the deals let the armed groups entrench themselves on the Pakistani side of the border and intensify their attacks across it into Afghanistan.
The new government's policy has also come under fire from the US and EU.
Washington expressed concern on Wednesday about the purported peace deal and urged Pakistan to continue to fight armed groups as part of Washington's so-called war on terror.
But Mohammed Sadiq, Pakistani foreign ministry spokesman, defended the use of negotiations with armed groups to curb a wave of suicide bombings.
"We believe that military action alone will not be effective in permanently ending the phenomenon of terrorism," Sadiq said.
Earlier, Mehsud's spokesman, Maulvi Omar, said the talks with the government were making progress.
"Talks are going well and the two sides have fulfiled their promises. We're very hopeful," Omar said.
The government had started withdrawing troops from different areas in South Waziristan and released some fighters, he said.
A military spokesman denied the army had pulled any troops out of the region but on Monday the authorities did release Sufi Mohammed, a senior Taliban leader accused of sending thousands of fighters across the border to battle US-led forces in Afghanistan.