Fazlullah's armed supporters have been fighting security forces in Swat since Friday, when the military raided the cleric's stronghold.
Shah Dauran, Fazlullah's spokesman, confirmed the ceasefire was in place and that the two sides would exchange the bodies of those killed.
"Later on we will hold negotiations with the government on establishing Islamic Sharia [law]" in the region, he said.
Authorities sent 2,500 paramilitary troops to Swat to fight supporters of Fazlullah, who has launched a Taliban-style Islamisation campaign in the once-peaceful district.
|"Later on we will hold negotiations with the government on establishing Islamic Sharia"|
Shah Dauran, spokesman for Maulana Fazlullah
Fazlullah is the leader of the banned pro-Taliban group Tehrik Nifaz-e-Sharia Mohammedi, or Movement for the Enforcement of Islamic Law.
Mohammed Ijaj, an official at Swat Hospital, said they had received 11 injured civilians overnight, and that all were in stable condition.
"We didn't hear any firing today," he said on Monday.
Over the weekend, the fighters captured a police post in the nearby village of Charbagh.
Violence first erupted in Swat in July, when armed men mounted attacks on the army after troops stormed the Red Mosque in Pakistan's capital, Islamabad.