A tourism banner on the side of a Grade II*-listed Liverpool City Council building is being removed because the authority hung it without permission.
The council said the sign on the Cunard Building was put up to coincide with the Champions League final in May.
But the authority failed to get planning permission to hang it on a listed building.
It said it would apply for permission to display it in the autumn when the Giants puppets return.
Liverpool City Council bought the Cunard Building - which provides office space - in 2014 for £10m.
The banner proclaims: "All great adventures begin and end in Liverpool."
A council spokesman said it "was first temporarily erected as a short-term tactical opportunity to promote the city for the Champions League Final when there were extensive international media in Liverpool, and then again for the visit of Channel 4 judges".
The city is one of a number of cities bidding to host Channel 4's new national headquarters.
Analysis: Claire Hamilton, Merseyside Political Reporter
Red faces all round at the council.
The Cunard Building is a Grade II*-listed building - a grade higher than Grade II but just below the highest Grade I level.
Along with the neighbouring Liver Building and Port of Liverpool Building, it is one of Liverpool's Three Graces.
It is also part of Liverpool's UNESCO designated World Heritage Maritime Mercantile City. The building has been owned by Liverpool City Council since 2014.
Historic England needs to be consulted on any alteration that would change the appearance of a Grade II*-listed building.
The spokesman said it "has been sensitively erected in a way that is sympathetic to the fabric of the building" and installed by a specialist local supplier who ensured no stone was drilled into.
He added: "Consent has been applied for it to be in place for the planned Giants event in October when the eyes of the world will be on us once again."
The Giants - a display of huge puppets by French company Royal de Luxe - will return to Liverpool in October following two previous visits in 2012 and 2014.