New Delhi, Apr 10 (IANS): Former Prime Minister and Congress leader Manmohan Singh paid tribute to veteran politician and Kerala Congress-Mani Chairman K.M. Mani, who passed away in Kochi on Tuesday.

"In his death, our country has lost a veteran political leader who served out country especially the state of Kerala for his entire life with dedication," Singh said in the letter to Mani's son Jose Mani.

He said Mani was very knowledgeable in financial matters and public affairs.

"I convey to you and other members of your family my heartfelt condolences on this bereavement. We prey to the Almighty to give all of you the strength to bear this great loss with courage and fortitude," Singh said.

Mani was suffering from a lung ailment and was in the hospital for the past one week. He had been unwell since January.

Mani joined the undivided Kerala Congress in 1965 and went on to become its undisputed leader. Over the years, his party underwent several splits.

Mani's record of being the longest-serving legislator in the Kerala Assembly began in 1967 when he represented his home constituency Pala in Kottayam district -- from where he won a record 13 elections.

First became a Minister in 1975, he served as Minister in six other governments, and holds the state record of having presented 13 budgets.