US President Joe Biden launched a diatribe against former President Donald Trump over his stance on the North Atlantic Treaty Organization, abortion rights, immigrants and other hot-button issues during the State of the Union address Thursday.

Referring to Trump as "my predecessor," not by name, Biden used the bully pulpit to criticize Trump and highlight his economic and other achievements, as he is gearing up for an all-but-certain rematch with Trump, now the only key Republican presidential candidate, in November.

Biden did not touch on North Korea during the televised speech to a massive audience of American voters, both Democratic and Republican, though he mentioned Russia's protracted war in Ukraine and the war between Israel and the Hamas militant group.

"Now, my predecessor, a former Republican president, tells Putin, 'Do whatever the hell you want,'" Biden said in an emphatic voice that appeared to belie his age of 81.

"A former American president actually said that, bowing down to a Russian leader. It's outrageous. It's dangerous. It's unacceptable," he added.

Biden was referring to Trump's controversial stump speech last month, in which Trump said that if reelected, he would "encourage" Russia to "do whatever the hell they want" to "delinquent" NATO members that fail to meet their defense spending commitments.

Calling for the congressional passage of an aid bill for Ukraine, Biden stressed: "We will not walk away. We will not bow down."

Brushing aside concerns about his age, Biden emphasized, "The issue facing our nation isn't how old we are. It's how old our ideas are."

Having cast Trump as a danger to democracy during his campaign, Biden used the speech to criticize what he termed an American story of "resentment, revenge and retribution."

"My lifetime has taught me to embrace freedom and democracy. A future based on the core values that have defined America -- honesty, decency, dignity, equality," he said. "Now (some) people my age see it differently."

Right after the Super Tuesday primary victories this week, Biden portrayed Trump as being "driven by grievance and grift, focused on his own revenge and retribution, not the American people."

The president also took a swipe at Trump over the abortion issue. Biden has been in support of abortion rights under the "fight for reproductive freedom," while Republicans have been calling for restrictions.

"Many of you in this chamber and my predecessor are promising to pass a national ban on reproductive freedom," he said. "My God, what freedom will you take away next?"

He railed against Trump's campaign remarks on immigrants as well.

"I will not demonize immigrants, saying they 'poison the blood of our country' as he said in his own words," Biden said. "I will not separate families."

As expected, he touted his economic achievements.

"It doesn't make the news, but in thousands of cities and towns, the American people are writing the greatest comeback story never told," he said.

"America's comeback is building a future of American possibilities, building an economy from the middle out and the bottom up -- not the top down -- investing in all of America -- in all Americans -- to make sure everyone has a fair shot, and we leave no one behind."

Biden mentioned South Korea as he touched on his efforts to reinforce regional alliances that he previously said had "atrophied" during Trump's presidency.

"I've revitalized our partnerships and alliances in the Pacific: India, Australia, Japan, South Korea, Pacific islands," he said.

Then, he stressed that he has made sure that the most advanced American technologies can't be used in China's weapons.

"For all his tough talk on China, it never occurred to my predecessor to do any of that," he said. "I want competition with China, but not conflict." (Yonhap)