Singapore's Deputy Prime Minister Heng Swee Keat said he was stepping aside as the country's designated future leader to let a younger person take over when current premier Lee Hsien Loong retires, according to his letter published in local media yesterday. "I would have too short a runway should I become the next prime minister then," Heng said in his letter. "We need a leader who will not only rebuild Singapore post-Covid-19, but also lead the next phase of our nation-building effort," he added. He is also set to give up his portfolio as finance minister, local media reported. He will continue serving as deputy prime minister. Why he took this decision is unclear but Heng suffered a stroke and collapsed during a cabinet meeting in 2016.