Protestors heckled New York City Mayor Bill de Blasio on Monday during a news conference at Trump Tower while he promoted his Green New Deal.

What are the details?

De Blasio had originally planned to hold the rally outside the 5th Avenue building but inclement weather forced the group to move inside the building that houses President Donald Trump's Manhattan home, the New York Post reported.

"Had the weather cooperated we would have been outside," de Blasio said.

Shortly before the mayor arrived, Trump Tower staffers reportedly turned up the music in the building's lobby. The playlist included Tony Bennett's "Stranger in Paradise" and Frank Sinatra's "I've Got You Under My Skin" blasted through the speakers during the event.

One protester rode up and down the escalator with a sign that read, "Worst mayor ever," according to the Post.

Some Trump supporters joined the protesters who booed and yelled, "You suck!" as the mayor tried to talk over the noise. Others held up "Trump 2020" signs.

Behind the mayor's podium, Juliet Germanotta, 37, held up a banner that read, "LGBT for Trump."

What did de Blasio say?

De Blasio told his supporters he plans to hold the Trump Organization accountable for what he claims it is doing to harm the environment.

"Clearly the Trump Organization is a little sensitive to the fact that we're calling them out for what they are doing to the climate but we are not backing down," the mayor said. "We will take your money. We will hold you accountable."

De Blasio said Trump's firm would be hit with seven-figure penalties if it doesn't retrofit eight of its buildings in New York City by 2030.

City officials claim that the Trump buildings emit 27,000 tons of greenhouse gases annually, according to the newspaper's report.

"We will not let you mortgage our future for your real estate," de Blasio continued.

De Blasio also called on his supporters to "scream loud enough so they can hear it all the way to the White House, 'Our planet, not your profit.'"

What else?

The mayor is expected to announce this week whether or not he will join the pool of Democrats who hope to make a bid for the White House in 2020.