KABUL: Taliban officials are due to meet a group of Afghan delegates in Doha this weekend as diplomatic efforts build to withdraw foreign forces from Afghanistan and end years of violence that continued this week with a devastating bomb attack in Kabul.

The weekend meeting, brokered by Qatar and Germany, will follow a separate strand of talks between Taliban militants and US diplomats this week aimed at agreeing a timeline for the withdrawal as well as security guarantees for a post-conflict Afghanistan.

Those talks have gone on for longer than expected as the two sides wrangle over the timeline and over counter-guarantees Washington is demanding against Afghanistan being used as a base for militant groups, including al Qaeda and Islamic State.

Pressure to reach an agreement was underlined on Monday when the Taliban claimed a truck bomb attack in Kabul that killed or wounded scores of civilians, many of them children.

Two senior officials said the two sets of meetings were deeply interconnected but were being kept separate as the groundwork was laid for full peace talks later.

"The idea is to prevent an overlap," one said.

A previously planned meeting in Qatar in April collapsed in fiasco before it even started amid arguments over the size of the proposed 250-strong Afghan delegation as well as over its status as a representative body.

This time, around 40 Afghan personalities and activists will fly to Doha but will not have any official status - a condition made necessary by the Taliban's refusal to deal directly with the Western-backed government in Kabul.

Invited by German and Qatari mediators, the identity of those taking part has not been made public. Markus Potzel, Berlin's special representative for Afghanistan and Pakistan, said in a statement they were participating "only in their personal capacity and on an equal footing".

Professional mediators from the Berghof Foundation, an independent non-profit German organisation, will assist during the talks but otherwise the meeting will include only Afghans in what is seen as a means of building confidence.

"The main aim of the intra-Afghan talks is to build trust between the warring sides as there will be no foreign government official present in the room," said a third source in Kabul.

The Taliban's main spokesman, Zabihullah Mujahid, said the talks with the US team, led by Washington's Afghan-born Special Representative Zalmay Khalilzad, were making good progress but no agreement had been reached.

As well as the withdrawal timeline and the guarantees on future security arrangements, US officials say they need an agreement on a ceasefire and on full talks between the Taliban and the Afghan government before any deal is finalized.

The involvement of Germany, the second-largest donor and an influential member of the 39-member NATO-led coalition in Afghanistan, follows concern among several US allies at being excluded from the direct talks with the Taliban.

Germany, which last year spent 23 billion euros ($25.76 billion) in integrating hundreds of thousands of refugees from countries including Afghanistan, Iraq and Syria, also has pressing domestic reasons for promoting peace. Next year, parliament will have to approve the continued presence of 1,200 German troops in Afghanistan.

US Secretary of State Mike Pompeo said on a trip to Kabul last week that the United States was close to finishing a draft agreement with the militants on counter-terrorism assurances, and he hoped a peace pact could be reached by Sept. 1.