The cease-fire became effective after 4 p.m. local time, said an official statement issued in Kabul.
Those violating the cease-fire will be severely dealt with, the government warned. The Afghan national army and national police were deployed to enforce the cease-fire.
"The president (Hamid Karzai) assures the people of Herat that the army and the national police will protect their lives and property and will not allow any one to harm the people," said the statement issued by his office.
Earlier reports from the area said U.S.-led coalition warplanes bombed the forces of an Afghan warlord near Heart.
The coalition bombs targeted the troops of Amanullah Khan, whose forces have been fighting Herat's governor, Ismail Khan.
The Karzai government is backing Ismail in the conflict and earlier this week government forces recaptured an airbase near Herat that had fallen to rebel forces.