Italian Eni and French TotalEnergies have begun exploratory drilling for natural gas off the coast of Cyprus in a block where a 2018 discovery was made.

The drillship Tungsten Explorer arrived off the coast of Cyprus Monday, to begin drilling in Block 6. According the Reuters, Eni Cyprus and TotalEnergies EP Cyprus BV are joint owners in the project. Eni is the operator.

The announcement comes Cyprus sees increasing natural gas exploration and discovery.

In March, ExxonMobil discovered high-quality gas with in-place resource estimates of 5 to 8 trillion cubic feet at its Glaucus-2 appraisal well in Block 10.

The increased exploratory activity is angering Turkey, due to the dispute over Cyprus. Offshore jurisdiction is disputed between Turkey and Greek Cypriots, causing Turkey to argue such activity encroaches on its national boundaries.

NATO is already in a political standoff with member Turkey over Finland and Sweden’s potential membership in the military alliance. Turkey is currently threatening a veto of any approval of membership for Finland and Sweden, demanding concessions from Western powers as it claims the two countries harbor “terrorists” from the Kuridstan Workers’ Party (PKK) and affiliated groups.

Some believe Turkey may also demand concessions over Cyprus in return for its any vote on NATO membership for Finland and Sweden. Hanging in the balance are the numerous defense contracts and military sales for western countries which will commence, to arm and equip the two countries to NATO standards, once their membership is approved.

Turkish action over what it perceives as illegal encroachments is not unprecedented. After Eni and Total announced the Calypso discovery in Block 6 in early 2018, the Turkish Navy blocked an Eni drill ship heading to Block 3, inside the EEZ.