Washington signed a key deal with the Taliban in February that promised the withdrawal of US and foreign troops from Afghanistan by next summer, provided the militants start talks with Kabul and adhere to other guarantees.

US General Scott Miller held discussions with the group in Doha on Friday night, US forces spokesman Sonny Leggett said.

"General Miller met with Taliban leadership last night as part of the military channel established in the agreement. The meeting was about the need to reduce the violence," he said.

Suhail Shaheen, a Taliban spokesman, said the meeting was about the "implementation of the agreement as well as its violations, particularly attacks and night raids in non-combat areas".

The Taliban has accused US forces of aiding the Afghan government with air support, causing civilian casualties. The US has denied the accusations.

The insurgents have also stepped up their attacks on Afghan security forces in government-controlled areas across the country.

A US defence official speaking to AFP accused the Taliban of making false allegations in a bid to pressure the US into pushing forward a prisoner release swap with Kabul.

The deal requires the Afghan government -- which was not a signatory to the accord -- to free up to 5,000 Taliban prisoners, and for the militants to release 1,000 pro-government captives in return.

A small Taliban team met with the government to discuss a comprehensive prisoner swap last week, but walked out of the talks soon after officials offered a piecemeal release of the prisoners.

The administration of President Ashraf Ghani on Wednesday released 100 low-risk Taliban prisoners followed by another 100 inmates the next day -- a move dismissed as "unacceptable" by the insurgents.