Complex sentence: In 1993, he was selected to receive the Israel Prize; after the then prime minster Yitzhak Rabin refused to participate in the award ceremony, Leibowitz declined to accept the prize.
Split into simpler sentences: In 1993, he was selected to receive the Israel Prize. However, after the prime minster Yitzhak Rabin refused to participate in the award ceremony, Leibowitz declined to accept the prize.