Biden called on Congress to send him a bipartisan national security bill amid Russia's ongoing war in Ukraine.

"If the United States walks away, it will put Ukraine at risk. Europe is at risk, the free world will be at risk," he said.

Biden also had a message for Russian President Vladimir Putin: "We will not walk away," he said to applause.

"We will not bow down! I will not bow down! In a literal sense, history is watching," Biden said.

Many Republicans have been increasingly skeptical of foreign aid to Ukraine versus spending on domestic priorities like the southern border. Biden and the GOP have not been able to agree on new immigration changes, despite a Biden-backed deal in the Senate.

Biden took his first jab at Trump of the night as he called on Congress to provide further assistance to Ukraine in its fight against Russian invaders.

"Ukraine aid is being blocked by those who want to walk away from our world leadership," he said. "It wasn't long ago, when a Republican president named Ronald Reagan thundered, 'Mr. Gorbachev, tear down this wall.'"

Biden continued, "Now, my predecessor, a former Republican president, tells Putin, 'Do whatever the hell you want.' That's a quote. The former president actually said that bowing down to a Russian leader. I think it's outrageous, it's dangerous and it's not acceptable."

Biden dubbed the current time an "unprecedent moment" in America, drawing parallels to his speech Thursday with that of former President Franklin Delano Roosevelt in 1941, right before the U.S. entered World War II.

"Tonight, I come to the same chamber to address the nation. Now, it's we who face an unprecedented moment in the history of the union. And yes, my purpose tonight is to wake up the Congress and alert the American people this is no ordinary moment either," Biden said.

The president warned that "freedom and democracy under assault" both "at home and overseas at the very same time," pushing for aid to Ukraine as it works to fight off Russia's invasion -- adding a warning as Congress proves unable to agree on a bill to send aid to Kyiv.

"If anybody in this room thinks Putin will stop at Ukraine, I assure you he will not," Biden said.

While Biden entered the U.S. Capitol House chambers for his State of the Union address, Secretary of Education Miguel Cardona was announced as the "designated survivor."

The designated survivor is a Cabinet member chosen to remain physically away from the president and vice president in case of an emergency or an attack during the State of the Union.

Cardona will go to an undisclosed location for the duration of the address.

Biden vowed to protect the Affordable Care Act, aka Obamacare, which he said provides health insurance to more than 100 million people who would otherwise be denied it due to pre-existing conditions.

"But my predecessor and many in this chamber want to take that protection away by repealing the Affordable Care Act," he said, as some in the chamber booed. "I won’t let that happen!"

"We stopped you 50 times before and we will stop you again!" he continued.

Republicans have for years tried and fail to repeal and replace the law, which has grown increasingly popular with the public.

In addition to protecting Obamacare, Biden said he wants to expand it by making permanent tax credits set to expire next year that save families $800 annually.