A prized communal toaster has sparked a standoff between council staff and Conservatives at Bradford town hall, with councillors vowing to hide the appliance from health and safety staff who say it is a fire risk.

Staff working in the Grade I-listed, 19th-century building are banned from using toasters because they are a fire hazard and contravene the council’s eco-friendly policies on energy use.

The rebellion by Conservative councillors was precipitated by an internal memo sent to all staff that said an environmental awareness officer had spotted contraband items.

An amnesty would be held on Monday, it said, for “all portable heaters, fans and toasters ... [which] do not comply with the council’s agreed recycling and heating efficiency policies”.

The leader of Bradford Conservatives, Simon Cooke, who calls himself on Twitter “scourge of the nannying fussbucket”, said he did not object to the council’s switch to recycling bins but the removal of his toaster was a step too far.

“The Conservative group has a small fridge, a microwave and a toaster, for the use of 23 councillors, which I do not consider to be extravagant or environmentally unfriendly,” he told the Bradford Telegraph and Argus.

“As we speak, staff throughout City Hall, are falling into three camps. Those that are bemused, those that are annoyed and those who are scurrying around trying to hide toasters and desktop fans. They may take our bins, but they will never take our toaster!”

Just done - for the first and probably last time - a photo call and interview while clutching a toaster. — Simon Cooke (@SimonMagus) December 9, 2015

A council spokeswoman confirmed the ban would be enforced. “Toasters are not permitted in council buildings, especially Grade I-listed City Hall, due to the risk of them setting off sensitive smoke detectors,” a statement said.

“These in turn trigger the fire alarms, leading to full building evacuations. False alarms are a waste of both council and fire service resources. We are also trying to encourage everyone to be energy-efficient, minimise waste and recycle as much as possible.

“This new policy is to make sure that it is as easy as possible for employees to be more energy-efficient, minimise waste and recycle at work to help the council to save money.”