PARIS - The Taliban in Afghanistan have not yet shown any sign they are serious about ending their 17-year insurgency despite US efforts to push a fresh peace process, the country's de facto prime minister has said.

Abdullah Abdullah, who serves as "chief executive" of the unity government in Kabul, struck a more sceptical tone about the prospects of a deal than President Ashraf Ghani, and his Western counterparts.

Ghani said earlier this month it was "not a question of if, but when" an agreement would be reached with the Taliban, while the US envoy to the country even raised the possibility of a breakthrough before presidential elections in April.

"Recently there are renewed efforts in terms of the international community and especially the United States," Abdullah said during an interview in Paris.

"We are not judging it too prematurely, but I would say that our experience as of now has been that they (the Taliban) have not shown any intention to get seriously engaged in the peace negotiations."

The comment on Wednesday came after the latest atrocity targeting civilians in Kabul when a bomber killed 55 people at a banquet hall at a ceremony to mark the birthday of the Prophet Muhammad.

Abdullah, a political veteran of the fight against Taliban rule in the 90s, called it "beyond comprehension".

Afghan security forces are also suffering an unprecedented level of casualties across the country where the Taliban and the Islamic State terror group are stepping up attacks.

Presidential candidate?

Returning to Kabul on Thursday after a three-day trip to France, Abdullah said he expected to be briefed fully about the latest round of talks between US envoy Zalmay Khalilzad and the Taliban, which are believed to have taken place in Qatar last week.

Whatever the outcome, he said Afghanistan should hold its presidential election as scheduled next April despite a recent upsurge in violence and suggestions from some that it should be delayed.

He downplayed any suggestion of a pre-election breakthrough with the Taliban.

"It will be very surprising if that happens, but should it happen ... that would be welcomed by the people of Afghanistan," he said.

Abdullah has kept up suspense about his own political ambitions after twice running for president in 2009 and 2014 in campaigns that ended bitterly amid accusations of fraud.

After being beaten in 2014 by Ghani, Abdullah agreed to become prime minister of the unity government in a US-brokered deal.

"I will actively be involved one way or another, but I have not made that final decision," Abdullah said when asked if he would run in 2019.

Agence France-presse