Greece will block any European Union peace deal for Libya, Prime Minister Kyriakos Mitsotakis said Thursday, unless a maritime deal between Turkey and Libya is scrapped.

"Greece at the level of a summit meeting will never accept any political solution on Libya that does not include as a precondition the annulment of this agreement," Mitsotakis told Greek television on Thursday.

"To put it simply, we will use our veto."

Greece says the deal setting border and energy exploration areas in the Mediterranean between Libya and Turkey is "unacceptable and illegal" because Greek claims in the Mediterranean are ignored.

Mitsotakis is also upset Greece is excluded from a peace summit on Libya to be held Sunday in Berlin. He says it is wrong not to invite Greece and plans to complain about it to German Chancellor Angela Merkel.

FILE PHOTO: Khalifa Haftar, the military commander who dominates eastern Libya, arrives to attend an international conference on Libya at the Elysee Palace in Paris, May 29, 2018.

Greece expelled the Libyan ambassador from Athens because of the deal signed with Turkey. It has also taken steps to boost ties with General Khalifa Haftar, head of a rival Libyan government whose forces have been fighting with those of the U.N.-backed administration in Tripoli.

Haftar is in Athens where he plans to meet with Mitsotakis on Friday.

Before flying to Greece, Haftar met in Benghazi with German Foreign Minister Heiko Maas, who tweeted that Haftar is willing to come to the Berlin conference and is committed to the cease-fire that took effect in Libya this week.

In Washington, a senior State Department official said Secretary of State Mike Pompeo would also attend the Berlin conference on Libya. The official said Pompeo would push for three things — the cease-fire, a withdrawal of all foreign forces from Libya and a return to the political process.