President Donald Trump continued his war of words with former Vice President Joe Biden in an exclusive interview with ABC News, hitting the Democratic presidential frontrunner for reversing some long-held views such as his position on a measure that bans federal funding for abortions.

“He has recalibrated on everything… Everything he’s said he’s taken back two weeks later because he’s getting slammed by the left. And he stuck with this stuff. He’s really stuck with this,” Trump told ABC News Chief Anchor George Stephanopoulos on Tuesday during an exclusive interview.

Biden recently announced he no longer supported the Hyde Amendment, which prohibits federal funding from being used to pay for abortions except for cases in which there was a threat to the patient's life, rape or incest. The law largely affects patients who are on Medicaid, meaning low-income patients have to pay for an abortion out-of-pocket.

The former vice president reversed his stance just one day after his campaign said his position on the amendment had not changed – and after being heavily criticized by several of his 2020 opponents.

Trump’s comments came the same day Biden turned up the heat on his attacks of Trump while both were in Iowa. In his remarks throughout the state, Biden called the president an “existential threat to America,” and “a genuine threat to our core values.” Trump’s comments were on Tuesday, the same day that Biden said the president presents an “existential threat to America.”

As the 2020 race heats up, President Trump has kept his focus on Biden, whom Trump has called “the weakest mentally.”

“He wanted to be the tough guy. He’s not a tough guy, he’s a weak guy,” Trump told Stephanopoulos in their interview.

Early internal polling data from the Trump campaign conducted in March and recently obtained exclusively by ABC News shows that the president trailed Biden in three key states that he won in 2016: Pennsylvania, Wisconsin and Florida.

Trump Campaign Manager Brad Parscale said those numbers are “ancient,” saying “Since then, we have seen huge swings in the President’s favor.”

Still, Biden and Trump’s attacks show no signs of slowing down. In a video released Friday, Biden slammed Trump for his admission during his interview with Stephanopoulos that he would accept information on an opponent from a foreign entity.

“Donald Trump doesn’t think it matters if candidates for presidency accept damaging information on their opponents from foreign governments. I believe he’s dead wrong.”

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