President Juan Manuel Santos signed the entry agreement in Paris on Wednesday whereby Colombia joined the Organization for Economic Cooperation and Development along with OECD Secretary-General Angel Gurria of Mexico.

In a brief welcome speech, Gurria emphasized that since Santos took office as Colombia's president he has kept OECD entry as one of his priorities, after concluding a peace agreement with the country's main leftist rebel group.

"In the entry process, Colombia has made impressive progress," said Gurria in a ceremony at which Lithuania also joined the organization, and which was attended by French President Emmanuel Macron, who delivered a speech defending multilateralism.

Santos, meanwhile, said that over the past eight years "Colombia has changed profoundly," and above all thanks to the end of the internal conflict "we're a country at peace," as illustrated by the holding of last Sunday's presidential election with the participation of the former FARC guerrillas, now an approved political party.

He acknowledged that "some reforms have not been easy" to defend in the face of public opinion but "the arguments that the OECD made to us were key."

Colombia will become the 37th member of the OECD when the entry instruments are ratified by the country's parliament and formally delivered to the organization.

Two other Latin American countries - Mexico (1994) and Chile (2010) - belong to the OECD, and Costa Rica is well on the way to joining later this year or early next year, Gurria said.