The DUP in Derry and Strabane say they are 'angered and dismayed' that the Derry City & Strabane District Council logo has been used to promote the Tony Taylor release campaign.
Photos in Monday's Derry News show the large posters in support of Mr Taylor being erected by individuals wearing Council-branded workwear.
The DUP's David Ramsey said: "These posters need to be removed immediately for the good of community relations.
"We will await the Mayor's response to this. He has continually shown a lack of understanding of the Mayoral role and a total disregard for unionism here locally.
"We will be asking council to undertake an urgent investigation into this situation and to take appropriate action in having these posters removed."
Mr Taylor was returned to prison two years ago this month after his parole was revoked for unspecified reasons. Politicians, clerics, trade unionists and community leaders have been campaigning for his release.
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