Chuck Schumer. Joshua Roberts/Getty Images Chuck Schumer delivered his first speech as Senate minority leader on Tuesday, spending most of the address from the Senate floor speaking about how Democrats would deal with President-elect Donald Trump.

The New York Democrat promised his party would not "be a rubber stamp" for Trump.

"It is not our job to be a rubber stamp," he said. "If the president-elect proposes legislation that achieves that — on issues like infrastructure, trade, and closing the carried interest loophole, for instance — we will work in good faith to perfect and, potentially, enact it. When he doesn't, we will resist."

Schumer said the new Senate would be an "accountability Congress" that "works to make sure" Trump keeps his campaign promises to "truly make America great."

"But we'll fight him tooth and nail when he appeals to the baser instincts that diminish America and its greatness — instincts that have too often plagued this country and his campaign."

Some of those specific promises, he said, include increasing the nation's GDP growth in excess of 5%, bringing down unemployment, getting tough on China, protecting Social Security and Medicare, and pushing an infrastructure package.

Schumer also criticized Trump for seeming "to be marching lockstep with a bullying, dissembling autocrat who has caused a great deal of trouble around the globe and here in America, Vladimir Putin," and said Democrats would respond if Trump doesn't select a "mainstream" justice to fill the Supreme Court seat vacated by Justice Antonin Scalia, who died last February.

Schumer called on Trump to reveal his healthcare plan amid his promise to repeal and replace the Affordable Care Act, commonly known as Obamacare.

"It's not acceptable to repeal the law, throw our healthcare system into chaos, and then leave the hard work for another day," he said.

Schumer said that through the transition, he believes Trump "seems to have forgotten" what got him elected president.

"The bottom line is, the president-elect ran as a change agent," he said. "He ran against the establishments of both parties. He promised to change the way America operates, to oppose elites, drain the swamp, and pay attention to working families."

The biggest sign of his forgetting, Schumer said, have been his Cabinet selections.

"Looking at the Cabinet — which is stacked with billionaires, corporate executives, titans of Wall Street, and those deeply embedded in Washington's corridors of power — it seems that many of his campaign themes are quickly being abandoned," he said. "He said he was going to un-rig the system. So far, it still looks rigged. Too many of his Cabinet picks support the same hard-right, doctrinaire positions that many in the Republican Party have held for years — policies that the American people have repeatedly rejected."

Trump's presidency "will not succeed" if he adopts "hard-right" policies, Schumer said.

Schumer then took aim at Trump's persistent use of Twitter, saying that "making America great again requires more than 140 characters per issue," and that "America cannot afford a Twitter presidency."

"There's nothing wrong with using Twitter to speak to the American people," he said. "It's a good use of modern media. But these issues are complex and demand both careful consideration and action. We cannot tweet them away."

"Tweeting 'very smart' to Vladimir Putin for ignoring American sanctions is no foreign policy," Schumer added later. "America does not conduct foreign policy by tweet, least of all by flattering Putin after our intelligence agencies have confirmed that Russia interfered in our election."

Trump recently told Schumer, according to The New York Post, that he was a bigger fan of the New York Democrat than he was of Republican leadership including House Speaker Paul Ryan and Senate Majority Leader Mitch McConnell. Trump and his family had donated more money to Schumer than to any other sitting senator.