Plymouth's three MPs have joined forces in a cross-party bid to ask English Heritage to reconsider its decision to list the city's Civic Centre.
The Civic Centre was opened by the Queen in 1962
Plymouth City Council wants to move out of the 14-storey Civic Centre which it says is "long past its sell-by date".
The government awarded the status after a request by "more than one person" and advice from English Heritage.
Gary Streeter, Alison Seabeck and Linda Gilroy are launching a petition for the decision to be reversed.
English Heritage says the Civic Centre, opened by the Queen in 1962, is a "very important post war building and is an iconic feature in the centre of Plymouth".
It recommended the listing on the basis that it was a complete set of civic buildings and had an "unusual richness of art work" and "very fine internal decoration".
The council opposed the listing when they heard it was being considered several months ago.
A Grade II listing recognises a site's special interest and warrants every effort to preserve it.