Athens: A highly unusual online exchange took place on Twitter between the prime ministers of Greece and Turkey before the former deleted his tweets - but only from the English version of his account.

The official English-speaking account of Greek prime minister Alexis Tsipras (@Tsipras_eu) posted four tweets addressed to his Turkish counterpart Ahmet Davutoglu, needling him about Turkey's downing of a Russian jet and Turkey's violations of Greek airspace.