BRASÍLIA, Brazil (AFP) — Brazil on Friday called for “restraint” as tensions flared in a territorial dispute between Venezuela and Guyana, with Caracas launching a major military exercise near the contested, oil-rich Essequibo region.

Venezuela’s President Nicolas Maduro on Thursday ordered thousands of troops to join the “defensive” exercise near the Guyana border, in response to Britain sending a warship to the area.

“The Brazilian Government is following the latest developments in the dispute surrounding the Essequibo region with concern,” said a statement from the foreign ministry.

“The Brazilian Government believes military demonstrations of support to either party should be avoided so that the ongoing dialogue process can produce results.”

Britain said Sunday it would divert the patrol vessel HMS Trent to Guyana, a former British colony, “as part of a series of engagements in the region during her Atlantic patrol task deployment”.

A Guyana foreign ministry source, speaking on condition of anonymity, told AFP the ship was due to arrive Friday and would be in its territory for “less than a week” for open sea defence exercises. The ship will not dock in Georgetown.

Responding to Maduro’s troop deployment, Britain said, “Venezuela’s actions against Guyana are unjustified and should cease.”

Maduro claims that Essequibo — which makes up about two-thirds of Guyana’s territory — is actually Venezuelan land, a decades-old contention that has flared since massive oil deposits were found in its waters.

Maduro’s Government held a controversial referendum on December 3 in which 95 per cent of voters, according to officials, supported declaring Venezuela the rightful owner of Essequibo.

He has since started legal manoeuvres to create a Venezuelan province in Essequibo and ordered the state oil company to issue licences for extracting crude in the region.

The rising tensions have raised fears in the region of a potential conflict over the remote area of 160,000 square kilometres (62,000 square miles).

Guyana, a former British and Dutch colony, insists the Essequibo frontiers were determined by an arbitration panel in 1899.

But Venezuela claims the Essequibo River to the region’s east forms a natural border recognised as far back as 1777.

Brazil’s President Luiz Inacio Lula da Silva has emerged as a peace broker of sorts, determined to prevent the current war of words over the disputed Essequibo region from escalating into something deadlier.

“If there’s one thing we don’t want, it’s a war in South America,” he said earlier this month.

The Brazilian statement called for both parties to respect an agreement reached after Maduro and Guyana President Irfaan Ali met on December 14 in St Vincent and the Grenadines, where they vowed, in a joint statement, not to resort to force to settle the dispute.

Prime Minister Ralph Gonsalves of St Vincent read the three-page statement, which included concrete measures to ensure tensions on the ground do not escalate suddenly.

But neither Venezuela nor Guyana agreed on the proper global jurisdiction to settle the territorial dispute over Essequibo, which makes up about two-thirds of Guyana’s territory.

Maduro, who has sought to rally support in his nation with the territorial claims, cast the summit as a triumph.

“Excellent day of dialogue!” Maduro posted on X, formerly Twitter. “We did it!”

The two sides pledged to resolve the dispute “in accordance with international law” but noted that while Guyana believes the International Court of Justice is the proper jurisdiction for the matter, Venezuela has rejected the body’s recognition over the issue.

Gonsalves said the both Georgetown and Caracas “committed to the pursuance of good neighbourliness, peaceful coexistence and the unity of Latin America and the Caribbean”.

The statement noted that the two leaders agreed to meet again within three months in Brazil,

Guyana’s president left the summit declaring that his nation will not cede its sovereignty over the region’s oil fields.

“Guyana has all the right… to facilitate any investment, any partnership… the issuing of any license and the granting of any concession in our sovereign space,” Ali said.

Guyana has taken the case to the UN Security Council and approached military “partners”, including the United States, which has carried out joint military exercises in Essequibo.

“The land boundary between Venezuela and Guyana should be respected unless — or until — the parties reach a new agreement, or a competent legal body decides otherwise,” US Secretary of State Antony Blinken told Lula, according to a State Department summary of a call between the two.

Lula has backed a peaceful solution and warned Maduro against “unilateral measures that could escalate the situation”.

Brazil, which borders both countries, has also reinforced its troops around the area.