President-elect Joe Biden's son Hunter said Wednesday that his “tax affairs” are under federal investigation, putting a renewed spotlight on the questions about his financial dealings that dogged his father's campaign.

In a statement released by the president-elect's transition office, the younger Biden said he learned about the investigation on Tuesday. He did not disclose details of the matter.

“I take this matter very seriously but I am confident that a professional and objective review of these matters will demonstrate that I handled my affairs legally and appropriately, including with the benefit of professional tax advisors,” he said in a statement.

Hunter Biden has long been a target of President Donald Trump and his allies, who have accused him of profiting off his political connections. Trump and his supporters also raised unsubstantiated charges of corruption related to Hunter Biden's work in Ukraine at the time his father was vice president and leading the Obama administration's dealings with the Eastern European nation.

The disclosure of the federal investigation led by the U.S. attorney's office in Delaware comes at an awkward moment for the incoming president, who is assembling his Cabinet. His pick for attorney general could have oversight of the investigation into the new president's son if it is still ongoing when Biden is sworn in on Jan. 20.

The transition team said in a statement: “President-elect Biden is deeply proud of his son, who has fought through difficult challenges, including the vicious personal attacks of recent months, only to emerge stronger."

Hunter Biden's attorneys did not immediately return phone messages seeking comment.