Greece, Israel and the United States have began a joint naval exercise around Crete and the eastern Mediterranean.

A day after Prime Minister Alexis Tsipras overhauled his negotiating team in an effort to speed up debt talks and unlock bailout funds benchmarked for Greece, the prime minister said on Tuesday that he might resort to calling a public referendum on any deal with international creditors.

The government's draft law based on "Varoufakis' list" of reform proposals will be submitted to Brussels Group on Wednesday, a senior Finance ministry official said after yesterday's meeting of the political negotiation group in Parliament.