Mr Mitsotakis will be meeting other leaders during the summit, including with Turkish president Recep Tayyip Erdogan. The agreement has led to a continuing dispute with Greece, Cyprus and Egypt over oil and gas drilling rights in the eastern Mediterranean.
Greece's prime minister, Kyriakos Mitsotakis, said he discussed the issue and other differences between Greece and Turkey with Erdogan on the sidelines of a North Atlantic Treaty Organisation summit Wednesday in London, adding that both leaders "noted disagreements".
The US completed its military pullback in north-eastern Syria, settling into a stable posture of 600 troops in the rest of the country after repositioning and reducing forces, Defence Secretary Mark Esper said. They two have also signed a security cooperation agreement.
"This agreement also amounts to a political message that Turkey can't be sidelined in the eastern Mediterranean and nothing can be really achieved in the region without Turkey's participation", Cagatay Erciyes, a senior foreign ministry official in charge of maritime and aviation boundary affairs, told a parliamentary committee on Thursday.
The deal sparked outrage in the Libyan parliament, which is located in the East and is in line with the self-styled Libyan national army led by General Khalifa Hifter.
Libya has been divided between two competing governments since 2015, one based in Benghazi in the east and the other based in Tripoli.
"Our recourse to The Hague has that very goal", he told journalists in Nicosia.
Greece has warned Libya's ambassador to Athens that if he failed to provide clarifications to the Greek government over the deal he could be expelled, a Greek government spokesman said on Tuesday.
Erciyes shared a map of Turkey's claimed exclusive economic zone, including reference points to the latest agreement with Libya as E and F.