Singapore's leaders have offered condolences to their Indian counterparts and the family of the South Asian nation's former president Pranab Mukherjee, who died on Monday, aged 84.

In a letter to Indian President Ram Nath Kovind yesterday, President Halimah Yacob exalted Mr Mukherjee for his distinctive contribution to India during his years of serving the country.

"India has lost one of her finest sons," Madam Halimah wrote.

"As India's 13th President from 2012 to 2017, Shri Mukherjee was down-to-earth and served with humility. His unwavering commitment to improve the lives of the Indian people will serve as a lasting beacon of inspiration to many," she added.

Prime Minister Lee Hsien Loong called the late president "a towering leader with a heart for the common man" and said he had personally known him for many years.

"He leaves behind a shining legacy of serving others, building consensus and rising above party politics. In today's world, these precious traits will be especially missed," Mr Lee said in a condolence letter to his Indian counterpart Narendra Modi.

Emeritus Senior Minister Goh Chok Tong sent condolences to Mr Mukherjee's son, Mr Abhijit Mukherjee, and said he remembered the late leader "as a stalwart leader and an exemplary diplomat".

"During our conversations, I was always struck by his political astuteness, sharp insights and unwavering dedication to India," Mr Goh wrote in his message.

"His ability to forge consensus on difficult issues bears testament to the deep respect that he commanded across the political aisle as well as his talent in unifying people. It is my hope that your father's legacy will continue to guide and inspire future generations of Indians," he added.

Mr Mukherjee, who was a finance minister before he became president, died at a New Delhi hospital where he was being treated for a lung infection.