NEW YORK — The Metropolitan Transportation Authority plans to withhold contractual raises from its workers, but the city's top transportation union says it's not backing down without a fight.

After the agency promised raises to a majority of its contracted work force last year, it implemented a "permanent wage freeze" this week.

It attributes this decision to its financial struggles brought on by the pandemic.

The freeze impacts contracts the MTA signed with Transport Workers Union Local 100 members in January 2020.

Union President Tony Utano took to Twitter on Thursday saying, "If the MTA thinks we are going to give up contractual raises, they are out of their minds."

That was posted in response to a tweet from its national association, Transport Workers Union of America, which says it will "never allow [the MTA] to steal wages from [its] members." Adding, "Frontline TWU workers have already paid a COVID-19 blood price and we're [damn] sure gonna deliver every dollar owed to our members."

TWU 100 represents more than half of all the city's transit workers.

MTA Chairman Pat Foye has not publicly commented on the "wage freeze".