The Taliban accused Afghan security forces Sunday of re-arresting insurgents who had been released as part of a crucial prisoner swap meant to kick-start peace talks.
They said the National Directorate of Security (NDS) had detained an unspecified number of insurgents released under the exchange programme, warning Kabul would "bear responsibility for the consequences".
"They are incessantly raided, detained and put behind the bar by NDS of the Kabul (administration)," Taliban political spokesman Suhail Shaheen said on Twitter.
Javid Faisal, the spokesman for Afghanistan's National Security Council, said the claim was "incorrect".
"It's their way of sabotaging the peace efforts and the peace talks that should start," he told AFP.
The prisoner swap has been a major stumbling block in getting Kabul and the Taliban to start peace talks.
Under a deal between the US and the Taliban, the Afghan government is supposed to release 5,000 insurgent prisoners while the Taliban free 1,000 government inmates.
Kabul has released most of the 5,000 but the NDS has said some of the Taliban inmates are returning to the battlefield.
Peace talks were originally supposed to begin March 10 but the deadline passed amid political disarray in Kabul and as the prisoner swap stalled.
In the months since, violence levels have soared across Afghanistan, with the Taliban carrying out near-daily attacks against security forces.
On Saturday, Faisal said the Taliban had killed 46 civilians in more than 400 "terrorist activities" in the past week.
"Peace requires commitment and will, which aren't visible in the actions of the Taliban," he said on Twitter.
Also Saturday, the US State Department said Zalmay Khalilzad, its special envoy who has been leading negotiations with the Taliban, will return to the region to "press for resolution of the remaining issues ahead of intra-Afghan negotiations".
"Although significant progress has been made on prisoner exchanges, the issue requires additional effort to fully resolve," the department said in a statement.
Khalilzad will visit Doha, where the Taliban have a political office, as well as Kabul and Islamabad before heading to Europe to brief NATO.
Pakistan support for any peace push is key, as the country has long been accused of backing the Taliban -- a claim Islamabad denies.