An Irish teenager has been charged with threatening to shoot and kill the president of Guyana.

The alleged threat was made during what his lawyer said was an alcohol-fuelled conversation with two bodyguards of the South American country's leader.

Glen Hanoman said the 17-year-old aid group volunteer was joking when he said he would shoot and kill President Donald Ramotar.

He said the teenager made the claim because he did not believe the two men were really bodyguards.

"He had been drinking beer since early the morning and had even mixed rum and beer and had them at the same time," Mr Hanoman said.

"I think that was the main factor at play when he argued with two of the guards."

The alleged incident occurred on Sunday at a rodeo in the rugged and remote Rupununi region along the country's border with Brazil.

The president was not there at the time.

The teenager pleaded not guilty to the charge before a local magistrate and was released on bail over the objections of prosecutor Vishnu Hunte.

"The threat was directed to none other than the president of Guyana, his Excellency Donald Ramotar, by a foreign national," Mr Hunte said.

"There is therefore likelihood that he may flee the jurisdiction since he is not a resident of Guyana."

The offence is a misdemeanour and the teenager, who is in Guyana for one year as a volunteer with the British group Project Trust, faces a fine if convicted.

Project Trust Chief Executive Ingrid Emerson said the charity sends teenagers on "structured international volunteering placements" all across the world.

She said: "During the course of the festivities a Project Trust Volunteer was arrested on suspicion of using threatening language. The 17-year-old has since been bailed.

"Project Trust is working closely with the volunteer's family and is in constant contact with the Irish Consul and the British High Commission."