GEORGETOWN, Guyana - Guyanese President Irfaan Ali discussed regional security on Tuesday with a senior US defense official as the South American country remains embroiled in a border row with Venezuela over the oil-rich Essequibo region.

Daniel Erikson, Deputy Assistant Secretary of Defense for the Western Hemisphere, was in Georgetown as tensions simmer over Essequibo, which makes up about two-thirds of Guyana's territory, but has long been claimed by Caracas.

"Discussions were based on areas of mutual interest including regional security, food security, climate change, information sharing, narcotics monitoring and disaster risk management," Ali wrote on Facebook of his meeting with Erikson.

Without specifically mentioning Erikson's visit to Guyana, Venezuelan President Nicolas Maduro on Monday accused his neighbors of acting "under the mandate of the gringos."

In Georgetown, Erikson also met with Carla Barnett, Secretary General of the Caribbean trade bloc known as CARICOM, according to the United States Embassy in the Guyanese capital.

Erikson's visit to ally Guyana comes a month after joint US-Guyana military exercises were denounced by Venezuela as a "provocation," stirring fears of an escalation in the neighbors' long-running row.

Caracas has long laid claim to Essequibo, which has been administered by Guyana for more than a century and is the subject of border litigation before the International Court of Justice (ICJ) in The Hague.

The region makes up about two-thirds of Guyanese territory and is home to 125,000 of the country's 800,000 citizens.

The dispute was revived in 2015 when US energy giant ExxonMobil discovered huge crude reserves in Essequibo.

In a major escalation, last month Maduro's government held a controversial, non-binding referendum which overwhelmingly approved the creation of a Venezuelan province in Essequibo.

At a meeting mid-December Maduro and Ali agreed not to resort to force to settle the dispute.

But the arrival two weeks later of a British warship off the coast of Guyana prompted Caracas to deploy more than 5,000 troops to the border for a "defensive" exercise.