This handout picture released by the Venezuelan Presidency shows Venezuela's President Nicolas Maduro (right) shakes hand with Guyana's President Irfaan Ali (left) during a meeting in Saint Vincent and The Grenadines on Dec 14, 2023. (PHOTO / AFP)

CARACAS - Venezuelan President Nicolas Maduro on Thursday ordered a "joint military action" by the Bolivarian National Armed Forces (FANB) in eastern Venezuela amid what he described as a "threat" from Britain.

The stationing of a British military ship in the waters of neighboring Guyana represents a breaking of the recent agreement Venezuela reached with the Guyanese government during the dialogue on Dec 14, said Maduro during a New Year's greeting speech to military personnel.

After diplomatic measures fell short, Venezuela would respond in a "proportional" manner and reserves all corresponding actions within the framework of international law, he said, adding that the British attitude was "unacceptable".

Royal Navy patrol vessel HMS Trent is visiting Guyana, a British ally and former colony, as part of a series of engagements in the region, the UK's defense ministry said in a statement earlier this month

One of the response measures implemented by the president was the immediate activation of the FANB joint military action General Domingo Antonio Sifontes 2023 in the eastern Venezuelan Caribbean and on the country's Atlantic front.

Royal Navy patrol vessel HMS Trent is visiting Guyana, a British ally and former colony, as part of a series of engagements in the region, the UK's defense ministry said in a statement earlier this month.

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"It is the breaking of the spirit of dialogue, diplomacy and peace of the agreements," Maduro said on Thursday. He said the deployment was "practically a military threat from London".

Maduro has ordered "the activation of a joint defensive action of the Bolivarian National Armed Forces" off the coast of Essequibo, he said in a state televised broadcast, but did not give more information.

Military leaders in Venezuela's east said during the broadcast that 5,600 uniformed personnel were ready for the operation.

In a statement, Venezuela's Foreign Ministry said the country "reserves all actions, within the framework of the Constitution and International Law, to defend its maritime and territorial integrity".

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Major oil and gas discoveries have been recently made in the 160,000-square-km Essequibo region.

With Reuters inputs