ATHENS—Greece’s parliament approved a raft of fresh taxes and austerity measures that the country must legislate to unlock further rescue loans, as the country’s most influential creditors—Germany and the International Monetary Fund—remain deadlocked over debt relief.

The measures were backed by the 153 lawmakers from the ruling Syriza party and its junior coalition partner, the Independent Greeks, securing the majority in the 300-seat parliament late Sunday.

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