The ceremony was held in the city of Cali in the west of the country. It was attended by President of Argentina Javier Milei, Chilean President Jose Antonio Kast, and Ecuadorian President Daniel Noboa, TASS reported.
De la Espriella secured victory in the runoff on June 21, receiving 49.6% of the vote.
Meanwhile, the US Department of State announced that Washington would spend $1 billion to support the new Colombian administration.
"The United States, working with Congress, intends to announce $1 billion in assistance as part of a security package to support President de la Espriella’s Administration in achieving our shared goals," the statement reads.
The funds will be directed to fight against organized crime and drug trafficking in the Western Hemisphere. Besides, some of them will be used to develop economy, trade, and mining.
Among the first steps made by the new president was the announcement that Colombia is joining the US-created alliance, Shield of the Americas.
"One of the first executive orders that I plan to sign after this ceremony will be the signing of the (act to join) Shield of the Americas - an initiative allowing to join forces, exchange strategic information, and step up joint measures by free countries against threats that affect national and regional security," he said in his inaugural speech.
In his words, Colombia, like other countries "is unable to defeat transnational criminal organizations on its own."
De la Espriella also pledged that his administration will "strengthen relations with all countries in the world on the basis of mutual respect."
MNA