US President Donald Trump called Shinzo Abe the greatest prime minister in Japanese history during a call between the two leaders, a White House spokesman said, days after the Japanese premier said he was stepping down for health reasons. The two men spoke at length, and Trump told Abe he had done a 'fantastic job' and that the relationship between their two countries was stronger than it has ever been, White House spokesman Judd Deere said in a statement. 'The President called Prime Minister Abe the greatest prime minister in Japan's history,' Deere said.