RAMALLAH, West Bank, Dec 9 (Reuters) - Palestinian President Mahmoud Abbas will call an early presidential and parliamentary election if he fails to form a new government to replace a Hamas-led coalition boycotted by the West, a senior Palestinian official said on Saturday. Yasser Abed Rabbo, a member of the Palestine Liberation Organisation's decision-making body, spoke to Reuters after the group deliberated how Abbas should proceed after he declared talks with Hamas for a unity coalition had hit a dead end. "If there is a political impasse, he will call for early presidential and parliamentary elections," Abed Rabbo said.