The European Union will impose an entry ban and asset freeze on two Turkish citizens involved in their country's disputed search for gas in the eastern Mediterranean.
Several diplomats in Brussels told AFP on Wednesday that agreement had been reached between EU members to begin imposing sanctions, and the decision will be reviewed by lawyers on Thursday.
Rich gas deposits have been found in the seabed in waters claimed by both Cyprus, an EU member state, and Turkey. Ankara is pushing its claim with test drilling that Brussels has deemed illegal.
President Recep Tayyip Erdogan's Turkish government has further heightened tensions by signing a maritime agreement with Libya that would extend its territorial waters in the Mediterranean but has been rejected by Greece.
France has vowed to step up its naval presence in the area and Turkey has sent forces to back up the UN-recognised government in Libya, despite an arms embargo.
Turkey insists its oil drilling is in accordance with international law and has argued that its un-recognised north Cypriot ally should have a share in earnings.
Cyrpus, however has signed contracts with the Italian, French and US oil giants Eni, Total and ExxonMobil to explore the deposits.
In July last year, EU foreign ministers decided to cut EU funds for Turkey, to reduce high level contacts and suspend negotiations on an air transport deal.
But, when confirmed, the new sanctions will be the first to target Turkish individuals involved in the project.
