'Pranab Da, you have always been a father figure and a mentor to me,' an emotional Prime Minister Narendra Modi wrote in a letter to Pranab Mukherjee on his last day as President.
The letter, which spells out the bond between the two leaders who come from different political ideologies, was shared by the former president on Twitter on Thursday.
'On my last day in office as the President, I received a letter from PM @narendramodi that touched my heart! Sharing with you all,' Mukherjee said in a tweet.
Modi responded by saying, 'Pranab Da, I will always cherish working with you.'
In the letter made public by Mukherjee, the prime minister said he had come to New Delhi three years ago as an outsider.
"The task before me was huge and challenging. In these times, you have always been a father figure and a mentor to me. Your wisdom, guidance and personal warmth have given me greater confidence and strength," he said.
Modi said Mukherjee's 'intellectual prowess' had been of constant help.
'You have been so warm, affectionate and caring to me. Your one phone call asking me 'I hope you are taking care of your health' was enough to fill me with fresh energy, after a long day at meetings or on a campaign tour,' he said in the letter dated July 24.
Mukherjee stepped down from office the next day.
'Pranab Da, our political journeys took shape in different political parties. Our ideologies, at times, have been different. Our experiences are also varied. My administrative experience was from my state, whereas you have seen the expanse of our national polity and politics for decades.
'Yet, such is the strength of your intellect and wisdom that we were able to work together with synergy,' Modi said.
The Bharatiya Janata Party leader praised the Congress veteran and former President for opening the Rashtrapati Bhavan to initiatives and programmes that recognised innovation and the talent of India's youth.
"You belong to a generation of leaders for whom politics was simply a means to selflessly give back to society. You stand as a great source of inspiration for the people of India. India will always be proud of you, a President who was a humble public servant and an exceptional leader. Your legacy will continue to guide us," Modi said.
The prime minister said he and all others would continue to draw strength from Mukherjee's democratic vision of 'taking everybody along'.
'Rashtrapati Ji, it has been an honour to work with you, as your Prime Minister,' Modi said.