The Colombian government and left-wing Farc rebels have signed a historic agreement deal that formally brings an end to 52 years of civil war.
The last of the major Cold War conflicts killed 260,000 people and left six million internally displaced.
President Juan Manuel Santos and rebel leader Timoleon Jimenez, known as Timochenko, used a pen made from a bullet to sign the deal.
The president says the deal will boost economic growth and unite the country.
“War is always more costly than peace,”
he said in an interview with the BBC, warning that it will take time for Colombian society to recover from more than five decades of conflict.
The deal must pass a referendum next week before it can pass into law. Polls indicate the majority of Colombians will vote for it, although there has been some opposition, led by two ex-presidents.
Under the deal, the Farc will be relaunched as a political party. The entire peace agreement will be put to Colombian voters in a popular vote on 2 October.
It comes after four years of talks in Havana, Cuba, between President Santos and Timochenko.
About 2,500 foreign and local dignitaries witnessed the signing ceremony in the walled, colonial city of Cartagena.
The president said the decision to use a bullet-pen was intended to illustrate Colombia’s transition from a country of bullets into a country of “education and future”.
Correspondents say President Santos has risked his political future on the success of the peace deal.
Farc rebels must now hand over weapons to the UN within 180 days.