Colombia is to halt bombing raids against left-wing Farc rebels for a month, President Juan Manuel Santos says, in a further sign of progress in the country's peace process.
Mr Santos said the move was in recognition of the fact a unilateral ceasefire declared by Farc was holding.
But operations against another guerrilla group - the National Liberation Army (ELN) - will continue.
Colombia's government and the Farc are holding peace talks in Cuba.
"In regards to the indefinite, unilateral ceasefire declared by the Farc on December 18, we must recognise that they have fulfilled it," Mr Santos said in a televised address.
"In order to start the de-escalation of the conflict, I have decided to order the minister of defence and armed forces commanders to stop bombing raids on Farc camps for a month," he added.
President Santos was critical of the smaller Colombian rebel movement, the ELN, saying the group had "increased its criminal activities".
His conservative opponents say halting the bombing will give the rebels valuable breathing space. Aerial raids have been a key component in the government's military campaign.
Key bombing raids
March 2008: Raid on Farc camp inside Ecuador kills Raul Reyes, member of the Farc secretariat
September 2010: Farc military commander Mono Jojoy dies in a bombing raid in Meta province
November 2010: Farc leader Alfonso Cano is killed in a bombing raid in south-western Cauca province
January 2014: Senior Farc rebel known as Romana survives a bombing raid in Meta province in which three of his bodyguards are killed
Farc negotiators have been engaged in peace talks with the Colombian government since November 2012.
They have reached partial agreements on a number of issues, including on the drugs trade, land reform and political participation, although they have yet to reach a final deal.
A peace commission composed of Colombian businesspeople and politicians is to be formed to help guide the process through its final stages, Mr Santos said in his speech.
Farc, the largest of Colombia's rebel groups, was founded in 1964 with the aim of installing a Marxist regime.
In the 1990s the group was forced to change tactics because of attacks from right-wing militias and became increasingly involved in the cocaine trade to raise money.
It has seen numbers drop from 16,000 to 8,000 in recent years, but rebels still control rural areas particularly in the south and the east.
Farc is listed as a terrorist organisation by the US and Europe.
At the weekend, the two sides announced plans to work together to clear unexploded landmines.
More than 220,000 people are estimated to have died in five decades of conflict.
November 2012 - Formal peace talks begin in the Cuban capital Havana between the Colombian government and the Farc
May 2013 - A deal is reached on land reform, one of the most contentious issues. It calls for fair access to land, and rural development, two key causes of the conflict
November 2013 - The two sides agree on the political participation of the Farc should a peace deal be reached
May 2014 - Both parties pledge to eliminate all illicit drug production in Colombia
December 2014 - The Farc declares a unilateral ceasefire
March 2015 - Both sides agree to work together to remove landmines. Colombia is one of the most heavily mined countries in the world