A diplomatic spat is brewing after Venezuelan naval vessels entered ExxonMobil’s Stabroek block offshore Guyana, reportedly threatening its floating production, storage and offloading vessels operating there including the Prosperity FPSO amid an escalating territorial dispute between the two nations.

Guyana's President Irfaan Ali on Saturday denounced an incursion by an armed Venezuelan naval vessel in disputed waters that are home to a mammoth offshore oil deposit being developed by ExxonMobil. In a televised address,

The United States issued a stern warning to the Nicolás Maduro regime on Saturday following reports that a Venezuelan patrol boat entered into Guyanaese waters, threatening ExxonMobil’s offshore operations.

The South American neighbours are involved in a long-running dispute about which country owns the oil-rich Essequibo area.

Guyana and Venezuela clashed again after the former complained of incursion into its oil-rich maritime territory, which then triggered a warning from Caracas against “dangerous provocation” based on “lies”.

The United States on Saturday denounced what it said were Venezuelan naval vessels "threatening" an ExxonMobil unit in maritime territory claimed by Guyana.

Guyana’s government said Saturday that a Venezuelan naval patrol ship entered its waters and approached a vessel contracted by Exxon Mobil (NYSE:XOM) in the Straboek block, according to media reports.