KABUL (REUTERS, AFP) - Taleban insurgents entered Kabul on Sunday (Aug 15) after taking control of all of Afghanistan's major cities, in a stunningly swift end to the country's 20-year war.

Here are some of the milestones in the Islamist militant movement's rapid advance in recent months.

April 14

President Joe Biden announces US troops will withdraw from Afghanistan from May 1 and ending on Sept 11, bringing America's longest war to a close. It was an extension of the previous withdrawal deadline of May 1 agreed between the US and the Taleban.

May 4

Taleban fighters launch a major offensive on Afghan forces in southern Helmand province. They also attacked at least six other provinces.

May 11

The Taleban captures Nerkh district just outside the capital Kabul as violence intensifies across the country.

June 7

Senior government officials say more than 150 Afghan soldiers are killed in 24 hours as fighting worsens. They add that fighting is raging in 26 of the country's 34 provinces.

June 22

Taleban fighters launch a series of attacks in the north of the country, far from their traditional strongholds in the south. The UN envoy for Afghanistan says they have taken more than 50 of 370 districts.

July 2

American troops quietly pull out of their main military base in Afghanistan - Bagram Air Base, an hour's drive from Kabul. It effectively ends US involvement in the war.

July 5

The Taleban says it could present a written peace proposal to the Afghan government as soon as August.

July 21

Taleban insurgents control about half of the country's districts, according to a senior US general, underlining the scale and speed of their advance.

July 25

The US vows to continue to support Afghan troops in the coming weeks with intensified air strikes to help them counter Taleban attacks.

July 26

The United Nations says nearly 2,400 Afghan civilians were killed or wounded in May and June in escalating violence, the highest number for those months since records started in 2009.

Aug 6

Zaranj, in the south of the country, becomes the first provincial capital to fall to the Taleban in years. Many more are to follow in the ensuing days.

Aug 8

The city of Kunduz in the north falls to the Taleban, despite the efforts of the Afghan security forces. Areas such as Lashkar Gan in the south saw intense fights as the Taleban attacked relentlessly. A massive car bomb detonated outside police headquarters on Aug 11 marked the epilogue of the battle, even though commandos were sent in to help local forces.

Aug 13

Four more provincial capitals fall in a day, including Kandahar, the country's second-biggest city and spiritual home of the Taleban. In the west, another key city, Herat, is overrun and veteran commander Mohammad Ismail Khan, one of the leading fighters against the Taleban, is captured.

Aug 14

The Taleban takes the major northern city of Mazar-i-Sharif and, with little resistance, Pul-e-Alam, capital of Logar province just 70km south of Kabul. The US sends more troops to help evacuate its civilians from Kabul as Afghan President Ashraf Ghani says he is consulting with local and international partners on the next steps.

Aug 15

The Taleban takes the key eastern city of Jalalabad without a fight, effectively surrounding Kabul. According to the UN Office for the Coordination of Humanitarian Affairs, 17,600 people arrived in Kabul by Aug 15, with thousands more in their footsteps. With close to no support from the authorities, most were forced to seek shelter in parks and public areas.

Aug 15

Taleban insurgents enter Kabul, an interior ministry official says, as the US evacuates diplomats from its embassy by helicopter.

Aug 16

People besiege the airport, the only exit route from the country, and chaos breaks out on the tarmac. Chaos ensues as people try to board the few flights available. US troops open fire, killing two armed men, the Pentagon says. All military and civilian flights are halted at Kabul airport.

Aug 16

Britain's Prime Minister Boris Johnson calls for G-7 leaders to hold a virtual meeting to discuss Afghanistan. Defence Minister Ben Wallace says the Taleban takeover is a "failure of the international community".

Aug 16

Breaking his silence on the US pullout after scenes of bedlam dominated television news channels for days, US President Joe Biden says he stands "squarely behind" his decision to withdraw US troops.

He blames the Taleban's takeover in Afghanistan on Afghan political leaders who fled the country and the unwillingness of the US-trained Afghan army to fight the militant group.