ExxonMobil has made the largest discovery of natural gas off the coast of Cyprus since it began drilling operations in 2011, Reuters reported.

The reservoir holds an estimated 5 trillion to 8 trillion cubic feet of gas, Cypriot Energy Minister Yiorgos Lakkotrypis said on Monday, Reuters reported. 

“This is the biggest find so far in Cyprus, and based on some official data it is one of the biggest finds worldwide in the past two years,” Lakkotrypis said. 

Cyprus already has a gas field that contains around 4 trillion cubic feet of gas, which was discovered south of the divided island in 2011, Reuters said. 

Nicosia’s energy exploration in the eastern Mediterranean has been a source of friction with Turkey, which also seeks to drill for gas reserves in waters its says is it territory and says the breakaway Turkish Republic of Northern Cyprus also needs its share of any revenues from the Cypriot finds.

Turkish Foreign Ministry spokesperson Hami Aksoy said ExxonMobil’s drilling did not help regional stability. Aksoy said he would take measures to guard “the rights and interests of the Turkish Cypriot people,” pro-government Daily Sabah reported . 

"We seize this opportunity to reiterate our warning towards the companies involved in the unilateral exploration and exploitation activities of the Greek Cypriot Administration," Aksoy said.

The gas drilling is taking place in what is referred to as the Cyprus exclusive economic zone (EEZ). Visiting U.S. Deputy Assistant Secretary of State Matthew Palmer on Wednesday urged restraint by all sides, according to Greek newspaper Ekathimerini . He said he supported the United Nations’ efforts to establish a bi-zonal federation on the island. 

Turkey disputes the Greek Cypriots’ rights to drilling in areas north of EEZ block 10, which Ankara claims is part of its continental shelf. The latest discovery of natural gas in block 10 could stoke tensions between Turkey, Cyprus, and Greece as Ankara plans its own drilling operations with the dispatch of two ships. 

Greece has entered agreements with Egypt, Israel, and Lebanon on drilling in block 10, and the operations are led by ExxonMobil and partners Qatar Petroleum. 

“We'd be interested in other opportunities offshore Cyprus and indeed the whole eastern Mediterranean,” said ExxonMobil Vice President Tristan Aspray, the Associated Press reported .