The ceasefire had been in place since December 2014.
Farc said it wanted a full bilateral truce but stressed it was not abandoning the long-running peace talks taking place in Havana.
Meanwhile President Juan Manuel Santos has called on the rebels to "speed up" the negotiations.
The two sides have been in on-off negotiations since 2012 in an attempt to end more than half a century of conflict.
Thursday's attack - in the country's south-western Cauca region - was the deadliest since the resumption of air strikes against the rebels last month.