Mayor Bill de Blasio hasn’t been shy in his criticism of President-elect Donald Trump.

Even as he pledges to work with the administration on issues like infrastructure, de Blasio will forego Friday’s inauguration, instead appearing at an anti-Trump rally in Midtown Thursday night and plotting strategy against what he called Trump’s extreme policies at a meeting this week of the U.S. Conference of Mayors.

"We are going to protect the progress we’ve made in this city," de Blasio said Monday on the Road to City Hall. "We’re going to protect the progress we’ve made in this country. We’re not going to take this lying down."

On his weekly appearance on the Road to City Hall, the mayor also addressed NY1’s report last week about young inmates at Rikers Island chained to desks for seven hours a day, a practice exposed by a member of the city Board of Correction.

"It's something that they have done recently, and a reason why they needed that extra protection in that situation — or why the people around them needed that extra protection. But it is, from everything I understand, far superior to a solitary confinement situation."

The mayor, meanwhile, touted what he suggested was a historic number of small-money donations to his re-election campaign while taking a swipe at challenger Paul Massey, a Republican real estate developer, who appears to have out-raised the mayor, reporting a haul of 1-point-6 million dollars over six months.

"It does not surprise me that a millionaire developer would be able to turn to lots of other people in real estate and in business and get a lot of large contributions," the mayor said. "I don’t think the people of this city are looking for a developer to lead us forward."

As for a move by some state lawmakers to block the city’s five-cent plastic-bag fee taking effect next month, the mayor stood firm.

"If some of the folks in the state senate oppose it, what’s their alternative?" the mayor asked. "The status quo is not acceptable."