Sharjah on Friday announced the death of Sheikh Mohammed bin Salem Al Qasimi and declared three days of mourning across the emirate.
Sheikh Mohammed was the brother of Sheikh Abdullah bin Salem Al Qasimi, Deputy Ruler of Sharjah, and Sheikh Abdulrahman bin Salem Al Qasimi.
Funeral prayers will be held after Asr prayers on Friday at King Faisal Mosque in Sharjah, and Sheikh Mohammed's body will be buried at Al Jubail cemetery.
Dr Anwar Gargash, diplomatic adviser to President Sheikh Mohamed, paid tribute to his "dear childhood friend".
"A cherished friendship and fond memories bound us together at Al Ahmadiya School, just as our neighbouring homes did in Deira," he said. "Those memories shall forever remain vivid in the soul, cherished and treasured."
Offering condolences, Mr Gargash prayed for Sheikh Mohammed bin Salem's soul and the Qasimi household.
In a statement announcing the death, the Diwan of Ruler Sheikh Dr Sultan bin Muhammad Al Qasimi extended condolences to Sheikh Mohammed's family and the wider Al Qasimi family, and prayed for the departed.
Condolences for men will be received from Saturday for three days at the residence of Sheikh Abdullah bin Salem Al Qasimi, Deputy Ruler of Sharjah, in Al Badee. Condolences will be received from 9am until Dhuhr prayers (12.18pm), and from Asr prayers (3.46pm) until Maghrib prayers (6.30pm) in the evening.
Condolences for women will be received at Sheikh Mohammed's residence in Al Tarfaana, Sharjah.
