Thousands of firefighters in town for the International Association of Firefighters convention marched on City Hall on Thursday. They chanted, "They say cutbacks, we say fight back."
IAFF General President Harold Schaitberger says if Nutter doesn't implement the award he will face "the full force of this international."
Earlier this month, an arbitration panel awarded the firefighters three years of 3 percent raises. That came after about 20 months of legal battles. Nutter has until next week to appeal or accept the terms.
Nutter's spokesman says the mayor is a strong supporter of firefighters and that they have every right to assemble.