The source said that Mawlawi Haibatullah Akhundzada, newly appointed to lead the terror group after a U.S. drone strike killed Mullah Akhtar Mohammed Mansour, will follow the militant policies espoused by founder Mullah Omar, who was killed in Pakistan in 2013.
The source said that the appointment of Akhundzada "will bring back the era of Mullah Mohammad Omar," referring to the one-eyed mujahedeen commander who led the group from its inception in 1994, with "a simple life, loyalty, and terror on enemies."
On Wednesday, as the new leader was announced, the group claimed responsibility for a suicide bombing in the capital that killed 10 people and injured four others, including two children.
However, Sayed Mohammad Akbar Agha, a founding member of the Taliban who lives in Kabul and says he knows the new leader, told CNN that Akhundzada is an educated and well-respected man, with more clerical and judicial experience than military, and brokering a peace with him could be easier than with Mansour.
The new Taliban leader belongs to the Noorzai tribe and is in his late 50s -- although the Taliban claim he is 47 years old -- and hails from the Taliban heartland in the Panjwai district of southern Kandahar province, according to Agha.
He became Mullah Mansour's deputy when Mansour succeeded Mullah Omar
, and subsequently took an active part in the day-to-day running of the movement, playing a key role in negotiating a ceasefire with a dissident Taliban faction earlier this year.
The senior religious cleric, who hails from its founding generation and was active in the 1980s mujahedeen struggle against the Soviet invasion in the 1980s, is seen as a uniter and his appointment shows the Afghan militant group hopes it will avoid succession disputes, analysts say.
Akhundzada was the "natural choice" to succeed Mansour
, who was killed in a drone strike in Pakistan on Saturday
, said Thomas Ruttig of the Afghanistan Analysts' Network.
Mullah Omar's presence looms large
Along with the stated desire to return to the hardline policies of the group's founder, a statement announcing his appointment also names Mullah Omar's son, Mawlawi Mohammad Yaqoob, in a deputy role.
"(Akhundzada) was already the senior deputy to Mullah Mansour. It's a clever choice because he is a religious scholar from the founder generation of the Taliban, and was close to Mullah Omar," said Ruttig.
"He may therefore be able to integrate the younger and more militant generation," he said.
"The Taliban understood that they needed a new consensus leader, and quickly, to prevent what was possibly the aim of the U.S. and Afghan governments -- to create turmoil around the succession."
Secret Shura meetings
The source described two secret meetings of the Shura (or supreme leadership) council of the Taliban's self-declared Islamic Emirate of Afghanistan that were held on Saturday and Tuesday, saying that at the first meeting the members initially favored Sirajuddin Haqqani, the leader of Haqqani terror network
, long aligned with the Taliban and al Qaeda, to be the Taliban's new leader.
On Tuesday, according to the source, Haqqani rejected the leadership position in favor of Akhundzada.
The statement announcing Akhundzada's accession also named Haqqani as a deputy.
Haqqani, who has a $10 million U.S. State Department bounty on his head
, leads an extensive family-based criminal network based primarily in North Waziristan, Pakistan. It held captured U.S. soldier Bowe Bergdahl
before he was repatriated in a prisoner swap.
Ruttig said the deputies represented the younger, more militant generation of the organization, which the Taliban was likely seeking to better integrate through their appointments.
Yaqoob's selection could help boost the Taliban's legitimacy in its southern Kandahar heartland, while Haqqani's appointment could have the same effect in the network's center of gravity in the east, he said.
Obama: Wasn't expecting a "liberal" replacement
U.S. President Barack Obama, when asked about his thoughts on the new leader, said sarcastically, "As I was saying to my team, I wasn't expecting a liberal Democrat to be the new leader of the Taliban."
Speaking to reporters during the G7 summit in Ise-Shima, Japan, Obama added that the Taliban "continues to be an organization that sees violence as a strategy for attaining its goals," but that the United States continues to ensure that the democratic process in Afghanistan is upheld and that "we're able to maintain the counter terrorism platforms."
Obama said he hopes but doesn't expect that there will come a point at which the Taliban -- or at least the "community that surrounds" it -- recognize their goals are best achieved through dialogue with the Afghan government.
Pakistan: Mansour death undermines peace
Pakistan's Ministry of Foreign Affairs released a statement confirming Mansour's death and reiterating its position that the drone strike that took out the leader was a violation of the country's sovereignty, "as well as breach of the principles of the United Nations Charter governing the conduct of the states." The statement also says that the ministry has conveyed its concerns to the United States.
It also says Pakistan believes the death of Mansour has further endangered an already fragile peace process, and "will further destabilize Afghanistan, which will have negative implications for the region.
"In our view there is no military solution to the conflict in Afghanistan. The use of force for (the) past 15 years has failed to deliver peace."