It also seems clear that the dispute, which centres on control of the Essequibo region in western Guyana, a sparsely populated area the size of Greece that constitutes about two-thirds of Guyanese territory, is mostly about oil. In 2015, the US oil giant, ExxonMobil, discovered a big field off Guyana’s coast, largely within its exclusive economic zone.

The discovery has swollen Guyana’s estimated oil reserves to about 11bn barrels.