ISLAMABAD -- The killing of al-Qaida leader Ayman al-Zawahiri in a U.S. drone strike in Kabul has put the Taliban in an awkward position between Washington and groups claiming the mantle of jihad in the region, analysts say, adding another element of uncertainty to Afghanistan's volatile mix.

The 71-year-old native of Egypt was one of the world's most-wanted terrorists for his alleged role in helping Osama Bin Laden plot the 9/11 attacks, though the U.S. has been hunting him since the 1990s. "Now justice has been delivered and this terrorist leader is no more," President Joe Biden said in a televised address from the White House on Monday, saying he had given final approval for the "precision strike" after months of planning.

Security experts consider Zawahiri's demise a severe blow to al-Qaida, as he had helped the group survive and spread in the years after Bin Laden's killing by U.S. forces in a raid in Pakistan in 2011. Zawahiri had a $25 million price on his head.

"Al-Zawahiri's death is a huge setback for al-Qaida, even though leadership decapitations do not matter too much to such groups, and a big win for U.S. counterterrorism efforts," said Abdul Basit, a research fellow at the S. Rajaratnam School of International Studies in Singapore. "His death will further weaken the global jihadist movement that is already split between Islamic State and al-Qaida."

The killing on Saturday came two weeks after a United Nations Security Council report confirmed that Zawahiri was alive and "communicating freely," following the Taliban's takeover of Afghanistan last year as U.S. troops withdrew. The report also observed a "consolidation of power of key al-Qaida allies within [the Taliban's] de facto administration," and that the terrorist network's leadership appeared to be playing an advisory role.

Zawahiri's presence in Kabul is sure to raise further questions about al-Qaida's relations with a Taliban regime already struggling under economic sanctions.

Washington and the Taliban had signed a deal in 2020 in Doha, paving the way for the withdrawal of American-led foreign forces in return for a guarantee that terrorist groups would not be allowed to operate on Afghan soil.

"By hosting and sheltering the leader of al-Qaida in Kabul, the Taliban grossly violated the Doha Agreement and repeated assurances to the world that they would not allow Afghan territory to be used by terrorists to threaten the security of other countries," U.S. Secretary of State Antony Blinken said in a statement on Tuesday.

Abdul Jabbar, a former operative in Afghanistan's intelligence service, told Nikkei Asia that Zawahiri was living in a wealthy neighborhood in Kabul, apparently in the confidence that the U.S. would not attack inside the country in light of the Doha deal.

The Taliban, for its part, condemned the drone attack as a "violation of international principles" and the Doha agreement, without directly acknowledging -- at least initially -- Zawahiri's killing.

While the U.S. and the Taliban criticized each other in public, security experts also believe Zawahiri's death might create problems for the Afghan rulers in the form of increasing pressure from jihadi groups.

The strike is likely to spark questions about how much security the regime provided.

In Afghanistan, al-Qaida heads a transnational collection of groups such as the Tehreek-e-Taliban Pakistan, the East Turkestan Islamic Movement, and the Islamic Movement of Uzbekistan. They helped the Taliban to capture most of the country last year.

"The jihadists, particularly al-Qaida fighters, will question the Taliban's commitment to jihad," the S. Rajaratnam School's Basit told Nikkei.

There is even speculation that the Taliban may have given up Zawahiri. Whether or not this is the case, experts see such talk fueling resentment.

Although the Taliban condemned the strike, the operative Jabbar told Nikkei that "it also seems that the Taliban's regime might have provided information to the U.S administration about al-Zawahiri in return for concessions to overcome problems, mainly the economic crisis, and [lack of] international recognition, to some extent," without elaborating on the basis for his assessment.

Basit argued that Zawahiri's frequent video releases, coupled with his relocation to Kabul, likely provided enough clues for U.S. intelligence.

The UNSC report also made note of Zawahiri's increased outreach to al-Qaida supporters via several video and audio messages, including a statement promising that the outfit was equipped to compete with the Islamic State -- an apparent bid to be recognized as the leader of a global movement.

Now the group Zawahiri led is once again on the ropes. Basit suggested that angry al-Qaida elements might be motivated to join ISIS-K, the Islamic State group branch active in South and Central Asia, which has been positioning itself as the region's last true jihadi movement.