Strike action by the Fire Brigades Union is damaging the good reputation firefighters have with the public, the Fire Minister said.
Members of the FBU are due to walk out from 6.30pm to 11pm today and again for two hours from 6am next Monday in a row with the Government over pensions.
Fire Minister Brandon Lewis said: "This strike action by the FBU is completely unnecessary and does nothing but damage the good reputation firefighters have with the public.
"The public will be baffled by the FBU's course of action when they hear that the deal being offered to firefighters gives them one of the most generous pension schemes in all the public sector."
Mr Lewis called on firefighters to reconsider their decision to strike and work towards a resolution.