The Taliban on Sunday ordered its fighters in Afghanistan to avoid gatherings of security forces and civilians, a day after a suicide bomber killed 25 people including members of the militant group celebrating an unprecedented ceasefire.

Saturday's attack on the outskirts of Jalalabad in the eastern province of Nangarhar marred an otherwise extraordinary Eid holiday as Taliban members hugged, posed for selfies and prayed with Afghan police and troops, politicians and civilians around the country — scenes that would have been unthinkable only a few days ago.

It was the first formal nationwide ceasefire since the 2001 US invasion and the display of jubilation and unity has fuelled hopes among war-weary Afghans that peace is possible.

The attack on a crowd celebrating the truce in Rodat district also wounded 54 people and was blamed by officials on the Islamic State group.

After the bombing the Taliban ordered fighters to stay at their posts or in areas under its control.

“To avoid harm to civilians, which God forbid we may cause (by our presence), all commanders should stop mujahedeen from attending such gatherings,” Taliban spokesman Zabihullah Mujahid said on Twitter. “The enemy has misused the ceasefire issue and there is a chance of more such bad incidents happening.”

Some Taliban commanders also told AFP they disapproved of their fighters visiting government-controlled areas and celebrating with security forces.

Mujahid made no mention of President Ashraf Ghani's announcement on Saturday extending the government's eight-day ceasefire with the Taliban that was due to end on Tuesday, and his call for the Taliban to do the same.

Ghani also said 46 Taliban prisoners had been released, a trend that “is going to continue”.

Other militants, including IS, are not part of the government's ceasefire.

The Taliban had agreed to a truce but only for the first three days of Eid, which started Friday, promising not to attack Afghan soldiers or police.

They would, however, continue attacking US-led NATO troops.

Ghani's extension of the ceasefire drew immediate international support and calls for the Taliban to reciprocate.

The European Union called the truce “historic”.

NATO's Resolute Support mission in Afghanistan and US Forces vowed to respect Ghani's announcement.

The head of Afghanistan's High Peace Council, charged with negotiating with the Taliban, called Sunday on the Taliban to “consider the wishes of the people” and extend its own ceasefire.

“If the ceasefire is extended, the next step will be the exchange of prisoners and then we will have a good base for the start of direct negotiations between the two sides, “Mohammad Karim Khalili told reporters.