Taliban and US negotiators have reportedly agreed parts of a potential peace deal a day after the Afghan insurgents signalled their commitment to talks by naming one of their most senior commanders as chief negotiator.

News of progress in the Qatar talks, and the appointment of Mullah Abdul Ghani Baradar, appeared to offer for the first time in nearly two decades a glimmer of real hope for a path to peace in Afghanistan.

“This has the potential to start the first serious peace process to end one of the biggest wars in the world. It’s monumental news, but we’re still at the early stages,” said Graeme Smith, Afghanistan analyst with the International Crisis Group. “We know the agreement has four parts: ceasefire, counter-terrorism, troop withdrawal, and intra-Afghan negotiations. Sequencing and timelines remain tricky.”

Baradar was a founding member of the movement and close aide to the first Taliban leader, Mullah Mohammed Omar. Once the Taliban’s military chief, he is hugely respected in the insurgent movement, but has also long sought a negotiated end to the war. He had reached out unsuccessfully to the US and the Afghan government in the past, and in 2010 he was arrested by Pakistani forces apparently angered by his unauthorised efforts to broker peace talks.

“[Baradar’s new role] is good news for the peace process,” Mohammad Umer Daudzai, the Afghan president’s special envoy on peace, told the New York Times. “He is one of the top two leaders. If he is leading the negotiations, he can make decisions more quickly.

He will now head the Taliban’s office in Qatar, the de facto embassy and international headquarters for the militant group, and site of recent talks with a US delegation.

The US peace envoy, Zalmay Khalilzad, arrived in the Gulf state on Monday for the week of talks, although he had met the Taliban several times before. Once the US ambassador in Kabul, he was asked this autumn by President Donald Trump to try to find an end to America’s longest war.

After several days of talks, the two sides had finalised some clauses to be included in a draft peace deal. The agreement included apparent concessions from both sides, including a commitment that foreign forces would be scheduled to withdraw 18 months after a deal was signed. The departure of western troops is a core Taliban demand.

In return the insurgents, who now threaten two-thirds of the country, would commit to keeping international terrorist groups, including al-Qaida and Isis, off Afghan soil or from using it to launch attacks abroad, one of Washington’s top priorities.

It was not clear if the US had fully accepted the provisions, and the absence of Afghan government representatives was a reminder that not all parties were present at the table. The Taliban have said they will not talk to Kabul officials, whom they denounce as a puppet government, until a ceasefire is struck.

Khalilzad is now heading to Kabul to brief President Ashraf Ghani on the talks, and while there is some scepticism in the presidential palace, there is also a growing desperation for peace among ordinary Afghans. A brief ceasefire last year was greeted with joy by both Taliban and government supporters, but since then violence has spiralled.

Ghani admitted on Friday that 45,000 members of Afghanistan’s security forces had been killed since he took power in 2014, and the UN has warned fighting is taking a record toll on civilians. For years, talks were rejected by one side or another in the bitter conflict – at various times the US-led foreign forces, Afghan officials and the Taliban themselves have turned down overtures from their enemies. And there were almost farcical errors, including when a shopkeeper impersonated a Taliban leader at talks with top Afghan and Nato officials, and the Taliban delegation that claimed to represent Mullah Omar when he had actually been dead for years.