Lee Kuan Yew was a visionary leader: Obama

US President Barack Obama hailed Lee Kuan Yew as a "visionary" who led his country from Singapore's independence in 1965 to build one of the most prosperous countries in the world today.

"He was a devoted public servant and a remarkable leader," Obama said in a statement after the death of Lee Kuan Yew, the first prime minister of Singapore - a position is served for three decades.

"Lee's views and insights on Asian dynamics and economic management were respected by many around the world, and no small number of this and past generations of world leaders have sought his advice on governance and development," Obama said.

"I personally appreciated his wisdom, including our discussions during my trip to Singapore in 2009, which were hugely important in helping me formulate our policy of rebalancing to the Asia Pacific."

"He was a true giant of history who will be remembered for generations to come as the father of modern Singapore and as one the great strategists of Asian affairs," Obama said.

Obama was joined by several other US leaders in expressing deepest condolences to the Lee family.

"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, Vice President Joe Biden said.

"He understood the importance of economic integration and effective governance to building a thriving, modern economy. He was a pragmatist, and sometimes uncompromising," he added.

US Secretary of State John Kerry said: "When Lee Kuan Yew became its first Prime Minister in 1959, Singapore was a newly independent nation with an uncertain future. By the time he left office 31 years later, the small island had been transformed into one of the most prosperous and dynamic countries in the world".

"Lee Kuan Yew exuded wisdom. The counsel I was fortunate to glean from conversations with him--about life and politics and global affairs--is among the most valuable and insightful I have received," Kerry said.

"He was, of course, a uniquely astute analyst and observer of Asia, and it is largely through his life's work that Singapore became one of the United States' strongest strategic partners in the region," he added.

"He was a visionary statesman whose uncompromising stand for meritocracy, efficiency and education transformed Singapore into one of the most prosperous nations in the world," said Christine Lagarde, Managing Director of the International Monetary Fund.

"His wisdom and leadership will be remembered by people all around the globe," Lagarde said.

Lee Kuan Yew, Singapore's founding father and first prime minister, died today at the age of 91 of severe pneumonia.

He had been hospitalised at the Singapore General Hospital for severe pneumonia since February 5.