President Joe Biden surprised much of the world when he visited Kyiv on Monday to commemorate the one-year anniversary of Russian President Vladimir Putin’s brutal assault on Ukraine.

The president’s team had previously stated he would visit Poland but not Ukraine; but the image of the US president with Ukrainian President Volodymyr Zelensky gave Mr Biden a chance to show his strength as commander-in-chief.

Mr Biden had repeatedly warned about the prospect that Russia would invade Ukraine in the weeks leading up to invasion on 24 February of last year. His ability to unite much of the international community behind supporting Ukraine, while making Russia a pariah, rehabilitated his image as chief diplomat after it took a hit during the United States’ exit from Afghanistan. As my colleague Andrew Buncombe writes, the images of Mr Biden walking through Kyiv offer a perfect image ahead of a potential re-election.

But while House Speaker Kevin McCarthy did not comment on the trip, many hardline House Republicans excoriated the visit. Representative Marjorie Taylor Greene, the right-wing conspiracy theorist who became one of Mr McCarthy’s closest right-wing allies, said it showed Mr Biden was putting “America last.” Representative Matt Gaetz, who led the charge to oppose Mr McCarthy’s bid to become speaker, criticised the fact it took so long for Mr Biden to visit the US-Mexico border, which the GOP has accused the president of making so porous.

The outcry from Republicans spells trouble for whether American support for Ukraine can continue in a divided Congress. Democratic control of the House meant that money for Ukraine came freely. At the end of last year, Congress included $45bn for Ukraine in its omnibus spending bill to fund the government. But that might be the last time that aid to Ukraine might come so freely.

While many Republicans continue to support Ukraine, particularly in the Senate, the handful of anti-Ukraine voices in the House GOP conference has only grown. Today, Republicans only hold 222 seats in the House, meaning that just a handful of hard-right Republicans could stonewall additional aid to Ukraine. Similarly, ahead of the 2022 midterms, Mr McCarthy told Punchbowl News last year that “Ukraine is important, but at the same time it can’t be the only thing they do and it can’t be a blank check.”

Where his predecessor Nancy Pelosi visited Ukraine last year to rally around Mr Zelensky, Mr McCarthy would likely face the wrath of his far-right caucus if he were to venture to Kyiv and be accused of being an “America last” Republican.

Russia’s war on Ukraine does not show signs of ending anytime soon, which makes US support for the country all the more vital. But Mr McCarthy’s desire to keep power after a drawn-out Speaker’s fight means he might not be willing to stir the pot for additional support at an incredibly crucial moment for Ukraine – and the US.