Taliban fighters freed in a prisoner swap before talks with the Afghan government have returned to the battlefield, a top Kabul official has said.
Abdullah Abdullah, who oversees the government's peace efforts, said some, though not the majority, of the 5,000 Taliban prisoners freed had returned to their fight.
"I do know that some have returned to the battlefield, which is a violation of the agreement that they had made," Dr Abdullah said during an online conference with the US Council on Foreign Relations.
"I do know that this has happened. I have examples in some areas, and these people have started insurgency in those—in those areas once they left."
Those freed swore not to take up arms again. The freed militants included several accused of notorious suicide bombings or assassinations and disagreement over whether they should be released helped delay talks for months.
Ten days after the negotiating teams finally met in Doha, Qatar, for their historic talks, the negotiating teams have yet to finalise an agenda or ground rules.
Dr Abdullah said talks had begun on a positive note though, as the delegations build familiarity with each other.
A ceasefire is expected to go to the top of the Afghan government's priorities when formal talks begin.
“Unfortunately, so far, the level of violence is very high and to a level that is not acceptable for the people," he said.
"I repeat my call to the Taliban themselves and also to all partners who have any leverage over the Taliban to press on that point.”
Zalmay Khalilzad, Donald Trump's special envoy for Afghanistan, told the House of Representatives that “by any measure, current levels of violence are too high”.
"We know that reductions are possible," Mr Khalilzad said.
America's own agreement with the Taliban will see all US troops quit the country by May 2021 if the militants stick to assurances they will not host terrorist groups like al-Qaeda.