Colombia's government and leftist FARC rebels have signed a historic ceasefire deal bringing them tantalisingly close to ending the longest running conflict in the Americas.
The accord, capping three years of peace talks in Cuba, sparked celebrations and tears of happiness among some in the Colombian capital on Thursday.
It sets the stage for a final deal to end a guerrilla war born in the 1960s out of frustration with deep socio-economic inequalities that outlived all other major uprisings in Latin America.
"May this be the last day of the war," said FARC commander Rodrigo Londono, better known by the nom de guerre Timochenko after shaking hands with Colombian President Juan Manuel Santos at a ceremony in Havana.
Mr Santos, 64, is half-way through his second term and has staked his legacy on peace in the face of opposition from sectors of the country who think the FARC should be crushed militarily.
"This means nothing more and nothing less than the end of the FARC as an armed group," Mr Santos said, adding that the final peace deal would be signed in Colombia.
"The children and youth of our country have never known a single day without the violence of the conflict. Neither have the adults."
In Colombia church bells pealed to mark the start of the signing and in the capital Bogota crowds gathered around giant TV screens dancing, cheering and clapping as the ceremony unfolded.
One placard read, "we've finished the war, now let's build peace."
About 1000 people gathered in the Plaza Bolivar, the city's main square, to celebrate despite rain. Some waved flags and balloons; others hugged and wiped their eyes.
Mr Santos' government says a final deal, which he said will be ready by July 20, would add one percentage point annually to economic growth in Colombia, which over the past two decades has turned itself around from a failing state to an emerging market darling.
Thursday's agreement went further than many had hoped, with the FARC committing to putting a final accord to the Colombian people in a plebiscite, a promise made by Mr Santos that had been a key sticking point.
But not everybody supports the peace process with former president Alvaro Uribe, the leading critic of the talks, saying the agreement is "surrender to terrorism" by Santos.