The Taliban on Saturday announced its first ceasefire in Afghanistan since the 2001 US invasion, with a three-day halt in hostilities against the country's security forces that was greeted with relief by war-weary Afghans.

But the group warned the suspension of fighting for the first three days of Eid, the holiday that caps off Ramadan, did not extend to “foreign occupiers”, who would continue to be targeted by the militants.

The unexpected move came two days after the Afghan government's own surprise announcement of a week-long halt to operations against the Taliban.

It is the first time in nearly 17 years of conflict that the militants have declared a ceasefire, albeit a limited one.

“All the mujahideen are directed to stop offensive operations against Afghan forces for the first three days of Eid-al-Fitr,” the Taliban said in a WhatsApp message to journalists.

But it added that “if the mujahideen are attacked we will strongly defend (ourselves)”.

The Taliban said “foreign occupiers are the exception” to the order sent to its fighters around the country. “Our operations will continue against them, we will attack them wherever we see them,” it said.

Hours before Saturday's announcement, Taliban militants launched two separate assaults on Afghan security forces in the western province of Herat and the northern province of Kunduz, killing at least 36 soldiers and police, officials said.

Even a brief cessation of hostilities would bring welcome relief to civilians in the war-torn country, where they are paying a disproportionate price in casualties as a result of the conflict.

'Only three days'

In recent years the resurgent militants, along with the Islamic State group, have stepped up their attacks on Kabul in particular, making it the deadliest place in the country for civilians.

“Only three days the Taliban are not killing us. The Taliban have won our hearts, if they strike a peace deal with the Afghan government, the Afghans will take them on their shoulders with love,” Shah Jahan Siyal, a resident of Nangarhar provincial capital Jalalabad, wrote on Facebook.

Dewa Niazai, a women's rights activist in the same province, posted: “Long live the Taliban! Finally we can breathe a deep sigh of relief on Eid days. I hope these three days of ceasefire turn to a permanent ceasefire.” But not everyone was satisfied.

“We shouldn't be happy with just a three-day ceasefire,” a woman in Kabul told AFP.

“It is not sufficient and our president also shouldn't be happy... We should reach for sustainable peace throughout the country.” President Ashraf Ghani welcomed the Taliban's move in a tweet from his official Twitter account. Defence ministry spokesman Mohammad Radmanish told Tolo News he hoped the “ceasefire continues”.

The UN Secretary-General's Special Representative for Afghanistan, Tadamichi Yamamoto, said in a statement he hoped the ceasefires would “serve as a stepping stone” towards peace talks between the Afghan government and the Taliban.