The Taliban have killed or wounded more than 400 Afghan security personnel over the past week, the interior ministry said Sunday, accusing the insurgents of increasing attacks ahead of expected peace talks.

Violence had dropped across much of Afghanistan since the Taliban announced a three-day ceasefire on May 24 to mark the Eid al-Fitr holiday, but officials have accused the insurgents of stepping up attacks in recent days.

"In the past one week, the Taliban carried out 222 attacks against the Afghan security forces, resulting in the death and injury of 422" personnel, interior ministry spokesman Tareq Arian said at a press conference.

He also accused the Taliban of targeting religious scholars in a bid to put "psychological pressure" on the Afghan government.

Bomb attacks on Kabul mosques that killed two prayer leaders this month were the work of the insurgents, Arian claimed.

"This has been the goal of the Taliban to target religious scholars, especially in the past two weeks," Arian said, accusing the militants of being an "umbrella group for other terrorist networks".

On Friday, four people including a prayer leader were killed when a blast ripped through a mosque in Kabul during the weekly prayers.

No group claimed that assault, which came just over a week after an Islamic State-claimed attack at a mosque on the edge of Kabul's heavily fortified Green Zone killed a prominent prayer leader.

The Taliban condemned both attacks.

After initially reporting a drop in overall violence following the ceasefire, National Security Council spokesman Javid Faisal on Sunday said the Taliban "have not reduced, but rather increased their attacks across the country".

The council on Saturday also charged that the insurgents had killed 89 civilians and wounded 150 in the last two weeks.

The accusations come after the government and Taliban signalled that they were getting closer to launching much-delayed peace talks.

President Ashraf Ghani has vowed to complete a Taliban prisoner release that is a key condition to beginning the negotiations with the insurgents aimed at ending nearly two decades of war.

The Taliban have largely refrained from launching major attacks on Afghan cities since February when they signed a deal with the US meant to pave the way for the talks.