Tsipras did much of the negotiating for the deal rather than Greece's Eurogroup representative, Varoufakis. But sources close to the government said this reflected Tsipras's need to win backing from Syriza's left wing and his right-wing coalition partner, the Independent Greeks party.

Their support will be crucial in maintaining government unity during negotiations for the long-term agreement.

Likewise Tsipras needs to keep public support. Costas Panagopoulos, who heads the Alco polling firm, said the initial reaction was relief that Greece would stay in the euro. Greeks might even accept Tsipras's change in language and assertions that the troika is no more. "It may sound odd but this could turn into political gains," he told Reuters.