Colombian President Juan Manuel Santos and opposition leader Alvaro Uribe met Pope Francis at the Vatican on Friday, as the government looked to build consensus for a peace deal with Marxist rebels.
On his third visit to the Vatican, Santos appealed to Francis for support in ending a 52-year war which has killed more than 220,000 people and displaced millions.
"We need your help," said Santos, who signed a modified peace deal in November after a previous pact was rejected in a plebiscite. He gave the pope a gift of a pen made from a machine gun bullet.
Francis, an Argentine who has helped broker diplomatic efforts in Cuba and Venezuela, then received right-wing Senator and former President Uribe, who has been one of the harshest critics of the new peace deal.
Uribe argues the new deal, which does not include opposition demands that Revolutionary Armed Forces of Colombia (FARC) rebels serve traditional jail sentences and are barred from forming political parties, is not tough enough on them.
The former allies also met Francis together for around 20 minutes. A photograph released by the Vatican showed them sitting side by side at a table in the pope's private study.
Santos won this year's Nobel peace prize for his efforts to reach an accord, under which some 7,000 rebels are now heading to special demobilization areas to hand in their weapons.
Francis has repeatedly expressed his support for the deal over four years of negotiations. At Friday's meeting, he presented Santos with a medal and copies of the three encyclicals produced during his papacy.