I assume you are talking about the claim that was made by George Papadopoulos, an adviser in Trump’s 2016 campaign who erved 12 days in prison for lying about his attemps to allegedly connect other campaign staff with officials representing Russia. He was pardoned by Trump near the end of Trump’s term as president.
In an April 12, 2021 tweet, widely ahared on Facebook, Papadopoulos stated:
"Biden is now withholding $150 million in aid from Ukraine as tensions with Russia grow. I mentioned this a couple weeks ago. He wants to pressure Ukraine to drop all criminal investigations into him and his son, Hunter. Where’s the media on this extortion attempt?"
The Facebook post was flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed.
There is no evidence Ukraine is conducting criminal investigations of the president or his son.
Federal law puts restriction on aid.
Congress approved and President Trump signed a bill appropriating $275 million for what is known as the Ukraine
Security Assistance Initiative. The secretary of defense can use the money to provide assistance, such as training and intelligence support, as well as weapons to Ukraine.
In March, the Defense Department announced it was releasing $125 million of the aid in training, equipment and advisory efforts as part of the U.S. commitment to provide "defensive lethal weapons to enable Ukraine to more effectively defend itself against Russian aggression."
The remaining $150 million will be provided when the Defense Department "certifies that Ukraine has made sufficient progress on key defense reforms this year, as required by the National Defense Authorization Act," the announcement said.
"The Department encourages Ukraine to continue to enact reforms that strengthen civilian control of the military, promote increased transparency and accountability in defense industry and procurement, and modernize its defense sector in other key areas in line with NATO principles and standards."
