Tens of thousands of people braved heavy rain and lined the streets of Singapore on Sunday to catch a last glimpse of founding prime minister Lee Kuan Yew as his funeral procession wound through the country he helped build.

Booms from a 21-gun salute reverberated around the country's business district, fighter jets flew overhead in a "missing man" formation and two navy ships near the marina made an "L" "K" "Y" signal with their flags as Lee's coffin was taken by gun carriage from the country's parliament to his state funeral.

The procession carrying Lee, who died last March 23 aged 91, will pass through Tanjong Pagar, the constituency he represented for 60 years, before continuing the 15.4 km trip to the ceremony at the National University of Singapore.