Afghanistan, which is seeking to open peace talks with militant Taliban insurgents, has faced an escalation of violence since NATO combat troops withdrew in 2014.

Here is a timeline of developments since then:

NATO combat forces leave

On December 31, 2014, NATO ends its combat mission in Afghanistan, launched after the September 11, 2001 attacks on the United States blamed on militants with bases in the country.

A US-led international force takes over. Dedicated to the assistance and training of some 350,000 members of the Afghan security forces, it reserves the right to intervene to support them.

Islamic State emerges

Several days later, a dozen former Taliban commanders from Afghanistan and Pakistan swear allegiance to the Islamic State (IS) jihadist outfit and its chief Abu Bakr al-Baghdadi.

IS fighters take root in the eastern province of Nangarhar, on the border with Pakistan, regularly clashing with the Taliban.

Brief fall of Kunduz

In October 2015, the Taliban win their biggest victory since the fall of their regime in 2001, seizing the northeastern provincial capital Kunduz for several days. It comes three months after the suspension of unprecedented talks between the group and Kabul.

The operation to retake control of the city is marked by a US air strike on a Medecins Sans Frontieres (MSF) hospital that kills 42 people, including 24 patients, and sparks international outrage.

In late 2015, the Taliban take control of large parts of Sangin district in Helmand, a heartland of the insurgency and centre for opium poppy cultivation.

Taliban, jihadists on the offensive

On July 23, 2016, IS -- until then confined to eastern Afghanistan -- claims its first large-scale attack in Kabul: 85 are killed in a twin bombing at a demonstration by the Shiite Hazara minority.

The Taliban also step up pressure on cities -- Lashkar Gah in August, Tarin Kot in September, Kunduz in October -- and multiply attacks on Afghan military bases.

On April 21, 2017, at least 135 young soldiers are killed in a Taliban attack on one of the biggest military bases in the country near Mazar-i-Sharif in the north.

Large-scale attacks increase in Kabul. Often perpetrated by suicide bombers, they are in turn claimed by the Taliban or the IS.

On May 31, 2017, a massive truck bomb attack in the city's diplomatic quarter kills at least 150 and injures 400, mostly civilians. It is the deadliest attack in the Afghan capital since 2001. No group claims responsibility.

US reinforcements

In April 2017, American forces use the most powerful of their conventional bombs on a network of tunnels and caves used by IS in Nangarhar, killing 96 jihadists.

President Donald Trump in August 2017 unveils a new strategy for Afghanistan that provides for reinforcements and an unlimited US military presence.

In mid-November, about 3,000 soldiers arrive to back up the 11,000 already on the ground.

Record civilian deaths

There is no let up in attacks: the number of civilians killed in the first six months of 2018 reaches a record of nearly 1,700, according to UN figures.

It is the worst toll in 10 years. Most of the attacks are carried out by IS.

A report published in May for the US Congress says the Afghan government controls only 56 percent of the country, the least since 2001, with 20 percent under the control of insurgents.

After an unprecedented three-day ceasefire in June, the Taliban step up their offensives. On August 9, they launch an attack on Ghazni, two hours from Kabul, managing for the second time in three months to penetrate the heart of a provincial capital.

Trial of strength

President Ashraf Ghani proposes peace talks with the Taliban in February 2018. Without responding officially, the insurgents let it be known that they are ready to negotiate but only with Washington, reiterating a demand for the withdrawal of foreign troops.

On June 7, Ghani announces a unilateral ceasefire with the Taliban for Eid al-Fitr, which marks the end of the Islamic month of Ramadan.

In turn, the Taliban decree an unprecedented ceasefire with Afghan forces but then refuse to extend it beyond three days.

In July, a US envoy meets Taliban officials in Qatar.

On August 19, Ghani proposes a three-month ceasefire with the Taliban, on the condition that they also stop fighting. There is no immediate response.