Speaker Nancy Pelosi (D-Calif.) took a jab at Republicans on Wednesday over COVID-19 vaccinations, arguing the GOP has been “delinquent” in embracing the science of vaccinations.

Pelosi was asked during a news conference about Senate Minority Leader Mitch McConnell (R-Ky.) running radio ads in Kentucky to encourage residents to get vaccinated.

“Well, I'm glad that he's doing those ads, long overdue,” Pelosi said.

“This was so self evident and so obvious. I don't know, maybe they were getting — to use your term — political backlash for not doing it as they now sadly see people suffering, in some cases, with long-term COVID. So certainly, the Republican Party has been delinquent in embracing the science that people need to be vaccinated,” she continued.

The comments come as Republicans encourage Americans to get vaccinated amid the rise of the delta variant, which is primarily impacting areas of the country with lower vaccination rates.

Centers for Disease Control and Prevention (CDC) Director Rochelle Walensky said last week that the variant accounts for 83 percent of all sequenced cases in the United States.

Recent polling has shown that Republicans were more likely to be hesitant about the vaccine, an issue that some GOP lawmakers are addressing. However, some Republican voices have gone farther than others in encouraging vaccination.

The Trump administration led efforts to quickly develop the vaccine last year, and some GOP leaders such as McConnell promoted the vaccine after getting the shot in December, though other voices in the party have continued to question its efficacy and criticize perceived government overreach.

The GOP Doctors Caucus last week endorsed the efficacy of vaccines while encouraging Americans to come to a personal decision after speaking with their doctors, saying they did not support efforts to make vaccines mandatory.

While Pelosi argued that McConnell running radio ads was “long overdue,” she said she was happy for those who will be “getting that message.”

“I'm so happy for the people who will be getting that message, who for some reason or other, may have thought that that politicians know more about science than a scientist,” she said.