Watch Live: 'I will not back down' Biden declares in fiery State of the Union address

• President Joe Biden delivered a fiery, partisan State of the Union address fit for an election year.

A spirited President Joe Biden delivered a fiery, partisan State of the Union address on Thursday, fit for an election year with enormously high stakes in a divided nation.

"Not since President Lincoln and the Civil War have freedom and democracy been under assault here at home as they are today," Biden said early in the speech.

"What makes our moment rare is that freedom and democracy are under attack, both at home and overseas, at the very same time," he said.

"Overseas, [President Vladimir] Putin of Russia is on the march, invading Ukraine and sowing chaos throughout Europe and beyond. If anybody in this room thinks Putin will stop at Ukraine, I assure you, he will not," the president said to cheers from Democrats and a applause to smattering of Republicans.

"My message to President Putin is simple. We will not walk away. We will not bow down. I will not bow down," Biden said.

The president also celebrated Sweden's ascension into NATO earlier in the day, as Swedish Prime Minister Ulf Kristersson sat to the left of First Lady Jill Biden in her guest box.

This is a developing story, please check back for updates.