The Taliban said Monday they had captured the last pocket of resistance in Afghanistan, the Panjshir Valley north of Kabul, as a top United States diplomat flies to Qatar to try and handle the aftermath of the chaotic American withdrawal.

The province was the last holdout of anti-Taliban forces in the country and the only province the Taliban had not seized during their sweep last month. Thousands of Taliban fighters overran eight districts of Panjshir overnight, according to witnesses from the area. They spoke on condition of anonymity fearing for their safety. Taliban spokesperson Zabihullah Mujahid issued a statement, saying Panjshir was now under the control of Taliban fighters.

"We tried our best to solve the problem through negotiations, and they rejected talks and then we had to send our forces to fight," Mujahid later told a press conference in Kabul. "With this victory, our country is completely taken out of the quagmire of war."

The so-called National Resistance Front (NRF) – made up of anti-Taliban militia and former Afghan security forces – defied the Taliban’s remarks of victory, asserting that opposition forces continued to fight and that its forces were present in "strategic positions" across the Panjshir Valley. However, earlier on Monday it acknowledged suffering major battlefield losses in Panjshir and called for a cease-fire.

The anti-Taliban forces had been led by the former vice president, Amrullah Saleh, and also the son of the iconic anti-Taliban fighter Ahmad Shah Massoud, who was killed just days before the 9/11 terrorist attacks in the United States. The whereabouts of Ahmad Massoud and Saleh remain unknown.

The group said in a tweet Sunday that spokesperson Fahim Dashty, a well-known Afghan journalist, and Gen. Abdul Wudod Zara had been killed in the latest fighting. Dashti was the voice of the group and a prominent media personality during previous governments. He was also the nephew of Abdullah Abdullah, a senior official of the former government who is involved in negotiations with the Taliban on the future of Afghanistan. Mujahid denied Dashti died in battle with the Taliban and claimed he was killed in an "internal dispute among two commanders in Panjshir," without offering any evidence to support that claim.

Following their lightning-fast rout of Afghanistan's army last month – and celebrations when the last U.S. troops flew out after 20 years of war – the Taliban turned to crush the forces defending the mountainous Panjshir Valley.

The valley is famed for being the site of resistance to Soviet forces in the 1980s and the Taliban in the late 1990s.

Taliban government

The Taliban have yet to finalize their new regime after rolling into Kabul three weeks ago at a speed that analysts say likely surprised even the hardline group themselves. Afghanistan's new rulers have pledged to be more "inclusive" than during their first stint in power, which also came after years of conflict – first the Soviet invasion of 1979, and then a bloody civil war. They have promised a government that represents Afghanistan's complex ethnic makeup, though women are unlikely to be included at the top levels. Women's freedoms in Afghanistan were sharply curtailed under the Taliban's 1996-2001 rule.

This time, women will be allowed to attend university as long as classes are segregated by sex or at least divided by a curtain, the Taliban's education authority said in a lengthy document issued Sunday. But female students must also wear an abaya (robe) and niqab (face veil), as opposed to the even more conservative burqa mandatory under the previous Taliban regime.

As the Taliban come to grips with their transition from insurgency to government they are facing a host of challenges, including humanitarian needs for which international assistance is critical. U.N. humanitarian chief Martin Griffiths has arrived in Kabul for several days of meetings with the Taliban leadership, which has promised to help.

"The authorities pledged that the safety and security of humanitarian staff, and humanitarian access to people in need, will be guaranteed and that humanitarian workers – both men and women – will be guaranteed freedom of movement," a statement from U.N. spokesperson Stephane Dujarric said. The Taliban spokesperson tweeted that the group's delegation assured the U.N. of cooperation.

On Monday the Taliban called on former members of the Afghan forces to integrate with the new hardline rulers.

"The Afghan forces who were trained in the past 20 years will be asked to rejoin the security departments alongside Taliban members," Mujahid said. The spokesperson added that any insurgency against their rule would be "hit hard," after earlier saying they had captured the Panjshir Valley.

"The Islamic Emirate is very sensitive about insurgencies. Anyone who tries to start an insurgency will be hit hard. We will not allow another," Mujahid said. Three weeks after seizing power but with no government so far announced, the spokesperson said an "interim" system would first be announced to allow for changes.

"Final decisions have been taken, we are now working on the technical issues," he said, according to remarks carried by Agence France-Presse (AFP). "We will announce the new government as soon as the technical issues are resolved."

Blinken trip to Qatar, Germany

The international community is coming to terms with the new Taliban regime with a flurry of diplomacy. U.S. Secretary of State Antony Blinken is due Monday in Qatar, which has been a key player in the Afghan saga.

Qatar, which hosts a major U.S. military base, has been the gateway for 55,000 people airlifted out of Afghanistan, nearly half the total evacuated by U.S.-led forces after the Taliban takeover on Aug. 15. Blinken will also speak to the Qataris about efforts alongside Turkey to reopen Kabul's airport, which is necessary for flying in badly needed humanitarian aid and evacuating remaining Afghans.

Blinken will then head Wednesday to the U.S. air base in Ramstein, Germany, a temporary home for thousands of Afghans moving to the U.S., from which he will hold a virtual 20-nation ministerial meeting on the crisis alongside German Foreign Minister Heiko Maas.

There has been no statement from Amrullah Saleh, Afghanistan's former vice president who had declared himself the acting president after Ashraf Ghani fled the country on Aug. 15 as the Taliban reached the gates of the capital. The Taliban subsequently entered the presidential building that day. In his statement, Mujahid sought to assure residents of Panjshir that they would be safe – even as scores of families reportedly fled into the mountains ahead of the Taliban's arrival.

"We give full confidence to the honorable people of Panjshir that they will not be subjected to any discrimination, that all are our brothers, and that we will serve a country and a common goal," Mujahid said in his statement. "There is no need for any more fighting," he added.

"All Panjshir people and those who live in Panjshir are our brothers and they are part of our country."