Asian shares turned lower and the euro slipped on Tuesday after the initial relief on Greece’s conditional bailout agreement gave way to caution, as investors waited to see if the Greek parliament would accept harsh austerity measures as part of the deal. Oil prices also skidded as the market awaited an announcement on a nuclear deal between Iran and six global powers that could lead to an easing of sanctions against Tehran and a resumption of its oil exports into an oversupplied market.