US President Joe Biden delivered an aggressive State of the Union speech on Thursday amid a rancorous, high-stakes political environment in an election year.

Biden, 81, used the speech as a vehicle to reverse perceptions of him amid falling polls and doubts about his ability to serve another four-year term.

"My lifetime has taught me to embrace freedom and democracy," he said. "To respect everyone. To give everyone a fair shot. To give hate no safe harbor.

"Now some other people my age see a different story: an American story of resentment, revenge and retribution," Biden said in an apparent reference to former president Donald Trump, his likely Republican opponent in what would be a rematch of the 2020 election. "That's not me."

Biden frequently criticized Trump throughout the speech, referring to him as "my predecessor" and shouted back at Republicans over Social Security and the border.

Trump, 77, provided a running commentary on Biden's speech in real time on his Truth Social platform, criticizing the 9:25 ET pm start to the speech scheduled for 9 pm. The president was frequently stopped by lawmakers who took selfies as he made his way up to the lectern in the House chamber.

"This is the longest walk in Presidential History - It is ridiculous!" Trump posted, calling the late start "VERY DISRESPECTFUL TO OUR COUNTRY!"

Among the pressing issues to Americans are illegal immigration and inflation, according to numerous polls.

Biden also is trying to navigate two divisive armed conflicts — in Ukraine and in the Gaza Strip between Israel and Hamas.

Continued military aid to Ukraine in its two-year battle with Russia has divided Congress and recently led to the derailing of legislation that included US border security measures.

Biden said the US should provide the weapons "Ukraine needs to defend itself", while also mentioning a comment by Trump in February that Russia "could do whatever the hell they want" to NATO countries that don't contribute enough to their defense.

Biden also railed against the Jan 6, 2021, attack on the US Capitol, which he called "the greatest threat to American democracy since the Civil War".

On abortion, a key election issue for Democrats, Biden said, "Women are not without electoral or political power" and "those bragging about overturning Roe v. Wade have no clue about the power of women in America. But they found out when reproductive freedom was on the ballot and won in 2022, 2023.

"We'll win again in 2024," he said about the issue.

He said that if Americans "send me a Congress that supports the right to choose, I promise you: I will restore Roe v. Wade as the law of the land again," he said.

Biden also touted the economy on his watch, along with the low unemployment rate and said 15 million new jobs were created "in just three years — a record".

He also said he was "ending" the fact that Americans pay more for prescription drugs than anyone else in the world and how the federal Medicare program would negotiate with pharmaceutical companies to lower the cost of prescription drugs.

The president engaged in a spirited back-and-forth with Republicans, accusing them of wanting to cut Social Security benefits. He also said he wanted to eliminate "junk fees" on credit cards.

"Send me the border bill now!" Biden bellowed about a measure that passed the Senate but was not taken up in the House.

House Speaker Mike Johnson released excerpts of the Republican response to the Democratic president by Senator Katie Britt, 42, of Alabama.

In the excerpts, she brought up border security: "President Biden inherited the most secure border of all-time. But minutes after taking office, he suspended all deportations, halted construction of the border wall, and announced a plan to give amnesty to millions.

Biden also said the US would build a floating pier off Gaza in the Mediterranean Sea to help deliver humanitarian aid to the war-torn area.