Turkey's President Recep Tayyip Erdogan also attended the ceremony at the Fatih Mosque in Istanbul.=
“We are facing a great calamity. Coronavirus has separated from us many of our companions,” Erdogan said.
Separate ceremonies were also held in the offices of Beyoglu Municipality, and Istanbul Metropolitan Municipality in Sarachane.
Topbas was hospitalized last November after contracting COVID-19. He was elected mayor of Istanbul in 2004 as candidate of the ruling Justice and Development (AK) Party, and maintained his position until 2017.
In 2004, he became the head of Istanbul-based United Cities and Local Governments, Middle East and West Asia Regional Government, and vice president of the United Cities and Local Governments (UCLG). He co-chaired UCLG 2007.
Topbas was the first Turkish politician to have won three consecutive local elections in Istanbul. He is survived by his wife and three children.