GEORGETOWN, Guyana (AP) -- Guyana's president 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.

President Irfaan Ali, in a televised address, said Guyana was hurriedly notifying all of its international allies, including the Trump administration, and had summoned Venezuela's ambassador in the capital, Georgetown, to lodge a formal protest.

"This incursion is a matter of grave concern," Ali said. "Guyana's maritime boundaries are recognized under international law. This is a serious development concerning our nation's maritime territory. We will not tolerate threats to territorial integrity."

The Trump administration, which this week took swift action to tighten sanctions on Venezuelan President Nicolás Maduro's government, immediately echoed Ali's concerns.

"Further provocation will result in consequences for the Maduro regime," the U.S. State Department said on X.

Ali said the Venezuelan vessel passed close to several huge vessels used to store oil being produced by three oilfields operated by Exxon and partners Hess Corp and CNOOC of China in the Stabroek Block containing an estimated 11 billion barrels of oil. He said several aircraft and marine vessels had been deployed to support the large number of drill ships, seismic vessels and support ships operating in the bloc.

Saturday's development came just two weeks after armed men, suspected Venezuelan pirates operating in the border Cuyuni River, exchanged gunfire with a Guyanese military patrol, injuring six soldiers, two of them seriously.

Since ExxonMobil made its major oil discovery in Guyana in 2015, Venezuela has revived a century-old territorial dispute with Guyana and taken steps to annex the remote Essequibo region that comprises about two thirds of Guyana's land mass.

The two neighboring states have feuded over land and maritime borders for decades as Venezuela claims that an 1890s boundaries commission cheated it out of the oil rich region. The area was administered by Britain for more than a century, and it has been under Guyanese control since 1966, when the nation gained its independence from the United Kingdom.