President Joe Biden on Tuesday continued his sharpened attack on what he's now calling the GOP's "ultra-MAGA" agenda as he pitched his plan to tackle inflation.

       His remarks came as the national average price of a gallon of gas hit a record high of $4.37 a gallon, AAA said.

       "I want every American to know that I am taking inflation very seriously," Biden said from the podium in the South Court Auditorium. "It is my top domestic priority."

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       Inflation is one of the Democratic Party's biggest problems heading into the 2022 midterm elections. Republicans have seized on higher costs to criticize Biden's domestic agenda while the White House is pinning the problem on supply chain issues, the ongoing coronavirus pandemic and Russia's invasion of Ukraine.

       Nicholas Kamm/AFP via Getty Images

       President Joe Biden arrives to speak about his plan to fight inflation and lower costs for working families, in Washington, May 10, 2022.

       Biden used his speech on Tuesday to tout what he said were recent accomplishments aimed at alleviating the increasing financial burdens on Americans, including a historic release form the Strategic Petroleum Reserve to offset soaring gas prices and reducing the national deficit. He also reiterated calls for Congress to pass other portions of his agenda that would lower the price of prescription drugs and other health care costs.

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       Biden also used the occasion to continue his ramped-up rhetoric against the GOP, accusing Republicans of having no concrete plan to address higher costs.

       "They have no plan to bring down energy prices today," Biden said. "No plan to get us to a cleaner energy independent future tomorrow."

       "My plan is to lower everyday costs for hardworking Americans and lower the deficit by asking large corporations and the wealthiest Americans to not engage in price gouging and to pay their fair share in taxes," Biden added. "The Republican plan is to increase taxes on middle class families, let billionaires and large companies off the hook as they raise prices and reap profits in record amounts. And it's really that simple."

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       Biden has used one proposal in particular as a target: GOP Sen. Rick Scott's pitch to have all Americans pay some income tax to "have some skin in the game, even if a small amount." That would mean a tax increase on Americans whose income is currently too low to owe federal income taxes.

       On Tuesday, Biden said Scott's plan will hurt frontline workers like firefighters and teachers.

       Despite Biden's focus on the plan, Scott's proposal hasn't been embraced by Republican leaders. Instead, Sen. Mitch McConnell made a point to distance himself from it shortly after it was announced.

       "If we are fortunate enough to have the majority next year, I'll be the majority leader, I'll decide in consultation with my members, what to put on the floor," McConnell said. "Let me tell you what will not be a part of our agenda. We will not have as part of our agenda, a bill that raises taxes on half the American people, sunsets Social Security and Medicare within 5 years. That will not be a part of the Republican Senate majority agenda."

       Before Biden spoke, Scott tweeted that Biden was "unfit for office" and should resign. Asked about that after he finished his remarks, Biden said, "I think the man has a problem."

       Biden's remarks on inflation come ahead of the release of April's consumer price index. The Bureau of Labor Statistics will announce those numbers on Wednesday morning. In March, the consumer price index spiked 8.5% from the year prior--the largest 12-month increase in 40 years.

       A recent ABC News/Washington Post poll found 68% Americans disapprove of Biden's handling of inflation. His approval rating on the issue was underwater by 40 percentage points. Republicans were more trusted by Americans to handle rising prices than Democrats, the survey found.

       ABC News' Ben Gittleson contributed to this report.