The Alliance Belfast Group Leader was speaking after the flag appeared in Island Street in the run up to the July fortnight.
“Alliance has received a number of complaints about the erection of the Confederate Flag in East Belfast, a flag which is perceived to racist,” said Councillor Michael Long.
“The flying of this flag is closely intertwined with historical slavery and racist tension, as can be seen by its glorification during recent racially-motivated attacks in the US.
“With rising racial tensions across Belfast, I am concerned the flying of this flag could lend legitimacy to those with intolerant attitudes.
“I hope the PSNI will act quickly to remove it.”