Dr. Olara Otunnu has joined Ugandans of all political shades in mourning the passing of President Yoweri Museveni's father, Mzee Amos Kaguta, whose death was announced Friday morning.

He specially lauded him for his positive influence "on the young man that would become the future president of the republic."

In his letter to the president dated February 22, the president of the opposition party Uganda People's Congress (UPC) paid homage to Mzee Kaguta for "a long and fruitful life, describing him as "a family patriarch."

"At this time of great loss and pain in your family, I convey to you my expression of personal sorrow and fellowship. My thoughts and prayers are with you personally and with the entire Kaguta family," Otunnu's letter - in which he addressed Museveni as "brother Yoweri" - reads in part.

"I salute Mzee Kaguta for a long and fruitful life, well-lived. I especially pay tribute to him for what turned out to be his unique gift to our country.

"He brought forth and nurtured the young man that would become the future president of the republic," the former UN Under-Secretary General and Special Representative for Children in Armed Conflict noted.

He added: "And I know from your personal testimonies that his influence and strength of personality have left indelible impact on your life."

Otunnu also entreated the "good Lord" to cover the entire Kaguta family with his love and solace during the "difficult period of bereavement and sorrow."

The UPC leader is an unwavering critic of the ruling NRM government, and he has on many occasions accused it of war crimes allegedly committed during attempts to quell the protracted Joseph Kony-led LRA insurgency in Northern Uganda.

Kaguta, 96, who was buried on Sunday at his home in Rwakitura, Nshwere in Kiruhura district, passed away at the International Hospital Kampala.

Tanzanian president Jakaya Kikwete, who currently chairs the East African Community (EAC), attended the burial.