Lib Dem politicians called in a decision record signed by deputy leader Coun Daren Hale for the Pacific Exchange offices on Hull’s High Street.
They were put up for sale by police commissioner Matthew Grove, who will use the £350,000 net proceeds towards a crime reduction fund, details of which will be announced tomorrow.
Groups across East Yorkshire and North Lincolnshire will be able to apply for a cut of a seven-figure sum.
The ten staff employed at the Commissioner’s office will be relocating to shared offices in the next few weeks, generating further savings.
Mr Grove said he was “leading from the front” in his efforts to cut costs, and had been able to generate “significant” savings against the running costs of the former police authority.
He said: “As soon as I was elected I made a promise to sell Pacific Exchange, the building I inherited from the former police authority, and use the proceeds to create a fund for local community projects that will help me deliver the outcomes in my Police and Crime Plan.”
The council has to save £48m and has had to make cuts to opening hours at museums in the city.
Labour claim they bought the building cheap and it will appreciate in value.
Pacific Exchange will be used to house the team working on the City of Culture 2017 plans and staff relocating as Kingston House and other offices close.
Lib Dem Group Leader Coun Mike Ross said the arguments put forward for its future use do not stack up.
He said: “Using it for City of Culture preparations demonstrates it is not a long-term plan.
“They need to take a long, hard look when making purchases like this. Are they acting in the best interests of the city or is it simply their own vanity project?”