On April 8, 2012, Israel declared German poet Günter Grass, recipient of the 1999 Nobel Prize in Literature, persona non grata because of his poem "What Must Be Said", which warned that Israel threatened an "already fragile world peace".
2012年4月8日，以色列宣布1999年诺贝尔文学奖获得者、德国诗人君特·格拉斯为不受欢迎的人，因为他在诗歌《必须要说的话（英语：What Must Be Said）》警告说，以色列威胁到了"本已脆弱的世界和平"。