Chile's candidate has emerged as the favourite to head the Organization of American States (OAS), after a Mexican representative pulled out of the race.
The deal was apparently struck after talks in Santiago
Chilean Interior Minister Jose Miguel Insulza is now expected to be elected when the OAS holds a vote on Monday.
Mr Insulza and his rival, Mexico's Foreign Minister Luis Ernesto Derbez, were deadlocked at 17 votes each after five ballots earlier this month.
US Secretary of State Condoleezza Rice has been backing Mexico's candidate.
The announcement was made by Colombia's Foreign Minister Carolina Barco, following intense talks on the regionally divisive issue that involved Ms Rice, both Mr Insulza and Mr Derbez and other diplomats from the Americas.
Ms Rice has acknowledged the leadership process has been divisive
"We are convinced that with this decision of unity, minister Insulza will be elected on Monday," Ms Barco said after talks in Chile's capital, Santiago.
During the earlier voting rounds, the region appeared to be splitting along geographic lines.
Most of South America and the Caribbean supported the Chilean candidate, while Central and North America backed Mexico.
Ms Rice at the time reiterated US support for the Mexican candidate, but also praised the Chilean nomination.
Traditionally, the US-backed candidate wins the leadership of the organisation, but it might not be the case this time, the BBC Clinton Porteous in Santiago says.
Our correspondent says Mr Derbez is seen as more conservative than Mr Insulza, who is a member of the socialist party
The post of the OAS chief has been vacant since October.