Tensions in Taliban ranks as head of militant group's Qatar office resigns

Kabul, Afghanistan (CNN)  The fractures in the ranks of the Taliban appear to be deepening after the announcement of the death of the Afghan militant group's longtime leader.

Syed Mohammad Tayab Agha, the head of the Taliban's office in Qatar and a very close ally of the late leader, said Monday that he had resigned, citing internal factional struggles to seize control of the leadership.

"In the current controversial situation, I am not supporting any side," Tayab Agha said in a statement. The Taliban's office in Qatar has been viewed as a potentially important element in any future peace talks with the Afghan government.

News emerged last week that Mullah Mohammed Omar, the Taliban chief who offered safe haven to former al Qaeda leader Osama bin Laden, had died in April 2013 in Pakistan.

The Taliban confirmed Mullah Omar's death soon afterward and said that Mullah Akhtar Mohammad Mansour would be the new leader.

Dissent from Mullah Omar's family

But not all members of the Islamic extremist group appeared to support that move.

Factions supporting Mullah Omar's relatives claimed that Mullah Mansour had seized the leadership. They issued a statement calling for no leader to claim power until the mourning period for Mullah Omar is over and a broad meeting can be held.

Supporters of Mullah Omar's family have claimed that the Mansour faction and their allies in the Haqqani Network, another militant group, are too closely aligned with Pakistan.

Tayab Agha appeared to obliquely reference that issue Monday by saying that "all responsible sides of the Taliban should transfer and regulate their affairs from inside the country."

Will the Taliban fall apart after Mullah Omar's death?

Talks with Afghan government in doubt

Tayab Agha was once the reclusive Mullah Omar's most trusted official. When Omar ran Afghanistan, Tayab Agha was his gatekeeper to the outside world.

A video was released Monday showing what appeared to be a gathering of Taliban members expressing support for Mullah Mansour as the new head of the militant group.

Before Mullah Omar's death was confirmed, Taliban representatives held talks in Pakistan with Afghan government officials about a possible peace process.

But Mullah Mansour has recently denied that the Taliban are attempting to work toward a peace process with the Afghan government.