Manila Mayor Lito Atienza and other officials opposed lawmakers proposal to rename the historic avenue, which extends from Manila City Hall to the Rotonda in Pasay City.
The Manila City Council is also set to ask the Senate to drop the proposal. Councilor Marlon Lacson, who is the majority leader, said all councilors have agreed to block the bill.
The avenue was named after American Gov. General William Howard Taft and lawmakers want it to be named in memory of the late Sen. Jose Diokno.
Lacson said renaming an avenue or a street in Manila is in violation of a city ordinance passed by the city council in 1999.
"In fact, relatives of the late Carlos P. Romulo has asked us to rename U.N. Avenue after him. We did not rename the avenue, instead we have a monument of the great man built along Roxas Boulevard," he explained.
Lacson said renaming the street after Diokno was not enough to recognize what the late nationalist did for the country.
He added that there are other roads which could be named after Diokno.
Meanwhile, the Manila police also expressed strong opposition to the plan to abolish the National Police Commission (Napolcom), which has the control and supervision of the Philippine National Police.
Without the Napolcom, the Manilas Finest Brotherhood Association Inc. (MFBAI) said there would be no check and balance in the PNP organization.
The Napolcom should remain as an agency that has control and supervision of the PNP, said MFBAI president SPO2 Antonio Emmanuel.