Islamabad, Pakistan - At least 20 members of the Pakistani Taliban, including the son of Tehreek-e-Taliban Pakistan (TTP) chief Mullah Fazlullah, have been killed in a US drone strike in the northeastern Afghan province of Kunar, according to a Taliban statement.

The fighters, including Abdullah, were killed in a strike on a TTP camp, the group said in a statement texted to local journalists in Pakistan's Bajaur district, which borders Kunar, on Wednesday.

According to the statement, 20 fidayeen, or suicide bombers, were killed, while another six fighters were wounded in the strike.

Prominent TTP commander Gul Muhammad and fidayeen trainer Yaseen were also killed in the strike, Pakistani newspaper Dawn reported.

Pakistan has often accused US and Afghan forces of not doing enough to target TTP forces resident on the Afghan side of the volatile Pakistan-Afghanistan border, where they fled following a series of military operations by Pakistan.

While violence has dropped in recent years, the TTP and its affiliates continue to carry out sporadic large-scale attacks targeting Pakistani security forces and civilians.

Violence casualties

At least 748 civilians and security forces were killed in violence perpetrated by the TTP and other armed groups, included armed Baloch separatists, in 2017, down from a peak of at least 3,739 in 2012, according to the South Asia Terrorism Portal, a New Delhi based research organisation.

Pakistan's military says that it has killed at least 4,000 fighters working for the TTP and its allies since 2013.

Al Jazeera is unable to independently verify that number, as access to the conflict areas is strictly controlled, and the identities of those killed are seldom revealed.

Pakistani Foreign Secretary Tehmina Janjua is in Washington DC this week for talks with the US aimed at lowering tensions between the two erstwhile allies.

In January, US President Donald Trump cut more than $1.1bn in military assistance to Pakistan over allegations that it was providing safe haven to members of the Afghan Taliban and Haqqani Network.

Pakistan denies the charges, alleging that it is being scapegoated for the failure of US-led coalition forces to secure Afghanistan after more than 16 years of war.

Recent diplomatic contacts appear to be softening the divide between the two countries.

On Monday, senior US State Department official Alice Wells said the US recognised that Pakistan had "legitimate concerns" regarding the situation in Afghanistan.

"They have concerns over border management; over the [Pakistani Taliban's] presence in ungoverned space in Afghanistan; refugee concerns," she said.

Additional reporting by Hameedullah Khan in Islamabad.