US President Barack Obama meets with then Singapore Minister Mentor Lee Kuan Yew in the Oval Office of the White House in Washington, Oct 29, 2009. [Photo/IC]

"Hillary and I mourn the passing of Lee Kuan Yew. Prime Minister Lee transformed Singapore into one of the world's strongest and most sustainable economies. He also firmly established his country as an important friend and partner of the United States.

"After leaving office, he continued to offer brilliant analysis and wise advice to those who sought it. We will always be grateful for our fascinating conversations with him over the years. Our thoughts are with Prime Minister Lee Hsien Loong, his entire family, and all the people of Singapore."

US vice-president Joe Biden

"Lee was a visionary leader who spearheaded Singapore's economic growth and helped it become one of the most prosperous countries in the world today. He understood the importance of economic integration and effective governance to building a thriving, modern economy. He was a pragmatist, and sometimes uncompromising. But his commitment to delivering excellence in public service was exemplary."

Japanese Prime Minister Shinzo Abe

"As the founding father of Singapore, who helped to create the foundations of the prosperity that Singapore enjoys today, he was one of Asia's great leaders.

"I would like to offer my deepest condolences to Prime Minister Lee Hsien Loong and his family and also my deepest sympathies to the citizens of Singapore."

Indonesian President Joko Widodo

"The late former PM is a close friend of Indonesia, known as the founder of modern Singapore. A great leader and statesman who loves his people, he is also known as an influential political figure in Asia.

"Under his leadership, Singapore has transformed itself to be the main economic hub in Asia and brought itself to par with the other developed countries."