JERUSALEM—Israel’s opposition leader moved closer to unseating Prime Minister Benjamin Netanyahu on Wednesday when he officially informed the country’s president that he has reached agreements with political allies to form a new government. About 30 minutes before a midnight deadline, Yair Lapid, according to a party statement, told President Reuven Rivlin in an email: “I am honored to inform you that I have succeeded in forming a government.” Rivlin, attending Israel’s soccer cup final at the time, congratulated Lapid by phone, according to his office. Lapid’s main partner is Naftali Bennett, who would serve as premier first under a rotation between the two men with Lapid taking over after about two years. Their coalition government would comprise a patchwork of small and medium parties from across the political spectrum, including for the first time in Israel’s history a party that represents Israel’s 21 percent Arab minority. But the new government, …