At a June 30 news conference in Kabul, Ashraf Ghani declared an end to the truce, but also called on the Taliban to resume peace negotiations.
"The cease-fire is over. The Afghan security and defense forces are allowed to restart their military operations," Ghani told reporters.
"It is now the Taliban's decision, whether they want to keep killing or join the peace process," he added.
Ghani told the news conference that the cease-fire had demonstrated that most Taliban members sought peace. He said that it was now up to the other side to "give a positive response."
"I am ready to extend the cease-fire anytime when the Taliban are ready," Ghani said.
Taliban fighters resumed fighting several days ago, launching attacks across the country that have seen scores killed or injured.
The cease-fire lasted 18 days in all, after it was extended once and coincided with a three-day Taliban truce.
Between June 15 and 17, videos and photos posted on news sites and social media showed soldiers and Taliban greeting and hugging each other and taking selfies in several provinces.
The three days of no fighting were unprecedented in the nearly 17-year conflict.
The renewed violence has dashed hopes that the truce would provide a clear path to peace talks. The Taliban has refused calls to lay down their arms until foreign forces withdraw from Afghanistan.
Militants, who have a small presence in Afghanistan, were not included in the cease-fire and they launched two deadly attacks on civilians during the Eid holiday that ended the holy month of Ramadan.
