A new row has erupted between the Cyprus government and neighbouring Turkey over oil exploration plans in the eastern Mediterranean.
Turkey has rebuked Lebanon for signing an agreement to delineate an undersea border with Cyprus - a deal that would facilitate oil exploration.
Turkey's foreign ministry said Ankara would "protect its rights and interests", the AP news agency reports.
The breakaway Turkish authorities in north Cyprus also condemned the deal.
The Cyprus-Lebanon deal was signed on 17 January. Cyprus signed a similar agreement with Egypt last year.
Reacting angrily on Monday, a spokesman for the Turkish Cypriot administration said "it is unacceptable that the Greek Cypriot administration attempts to sign agreements with neighbouring countries as if it is representing the whole of the island".
Earlier, Turkish Cypriot leader Mehmet Ali Talat insisted that "we are partners in everything that goes on in Cyprus and will not allow our interests to be harmed".
A Cyprus government spokesman shrugged off the Turkish anger, saying Cyprus "has no intention of getting involved in a public discussion on this issue".
"If Ankara has made strong or weak representations to Lebanon, I believe that Lebanon itself will reply," said the spokesman, Christodoulos Pashiardis.
Reuters news agency says studies suggest there could be undersea reserves of up to eight billion barrels of crude oil worth about $400bn off Cyprus.