Right-wing candidate Abelardo de la Espriella, who received the backing of U.S. President Donald Trump, won Colombia's presidential runoff election, according to preliminary results released on Sunday.

Data from Colombia's National Civil Registry showed that with 99.91% of ballots counted, De la Espriella secured 49.65% of the vote, ahead of ruling coalition candidate Ivan Cepeda, who received 48.70%.

The margin between the two candidates stood at approximately 246,000 votes, while voter turnout reached 61.5%, election authorities said.

Addressing supporters in the Caribbean coastal city of Barranquilla, De la Espriella declared victory and said his campaign had prevailed despite what he described as pressure, corruption and the influence of armed groups.

President Gustavo Petro urged caution following the release of the preliminary results, saying allegations of irregularities had emerged at some polling stations and that the final outcome would only be determined after the official legal count is completed.

Petro also called for national unity, noting that the election highlighted deep political divisions within the country, and urged Colombians to remain calm while the counting process continues.

Cepeda acknowledged the preliminary results but announced that his campaign would challenge the outcome in approximately 33,000 polling stations. He said the election had produced one of the narrowest margins ever recorded in a Colombian presidential runoff and pledged to pursue all available legal avenues.

The leftist candidate added that teams of lawyers and election observers would review voting records and requested that all contested polling stations be examined during the official count.

De la Espriella, who also led the first round of voting in May with 43.7% support, centered his campaign on security policies and efforts to combat armed groups.

The politician, who holds both Colombian and U.S. citizenship and is widely known by the nickname "The Tiger," is expected to take office on Aug. 7, succeeding President Gustavo Petro if the result is formally confirmed.

Trump congratulated De la Espriella on social media, writing that he had "won in tremendous fashion."(ILKHA)