Asked by a reporter if he would consider reversing the decision once in office, he responded: “I might yeah. I thought it was a very stupid thing to do.”
He also incorrectly claimed that Joe Biden’s decision to allow Ukraine to strike targets on Russian soil with US weapons triggered the deployment of North Korean soldiers.
The outgoing President has said he made the move because of Russia’s decision to deploy North Koreans on the battlefield.
Trump has previously claimed that the decision by the outgoing President risked “escalating this war and making it worse”.
Trump has vowed to end the war between Ukraine and Russia quickly after taking office for a second time, without setting out how he plans to do so.
On Monday, the Republican said he would speak to both Ukraine’s Volodymyr Zelenskyy and Russia’s Vladimir Putin to end the war because the images of conflict had troubled him.
“It’s got to stop,” he told reporters.
When challenged whether he would force Ukraine to cede territory to Russia, he suggested many of the towns being fought over had been reduced to rubble.
Trump said: “I mean, there are cities that there’s not a building standing, it’s a demolition site.”
He also said he had been shown pictures of body-strewn battlefields that reminded him of some of the grisly photographs from the 1861-1865 American Civil War.