Sen. Josh Hawley, R-Mo., is calling for President-elect Joe Biden to promise not ro remove investigators from the Hunter Biden case, and to answer questions under oath if needed, amid growing pressure from Republicans on Biden over his son’s financial and business dealings.

“Joe Biden needs to pledge today that he will cooperate with the federal investigation and answer any questions under oath,” Hawley said Thursday, according to The Associated Press, “and that if he is sworn in as president, no federal investigator or attorney working on the Hunter Biden criminal case will be removed.”

JOE BIDEN BREAKS SILENCE ON HUNTER FOR FIRST TIME SINCE FEDERAL TAX INVESTIGATION SURFACED

Hunter Biden confirmed this week that the U.S. Attorney’s Office in Delaware is investigating his “tax affairs,” and said he is “confident” he handled his affairs “legally and appropriately.”

“I learned yesterday for the first time that the U.S. Attorney’s Office in Delaware advised my legal counsel, also yesterday, that they are investigating my tax affairs,” Hunter Biden said in a statement. “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.”

A well-placed government source told Fox News that Hunter Biden is a subject/target of the grand jury investigation. The source said President-elect Biden is not a subject of any grand jury investigation at this time.

HUNTER BIDEN 'TAX AFFAIRS' UNDER FEDERAL INVESTIGATION

The source also told Fox News that this investigation was predicated, in part, by Suspicious Activity Reports (SARs) regarding suspicious foreign transactions. 

Another source familiar with the investigation told Fox News that the SARs were regarding funds from "China and other foreign nations." Two sources familiar with the investigation told Fox News that the investigation includes looking at the laptop purportedly belonging to Hunter Biden. 

Republicans are likely to zero in on the revelations in the coming months, with President Trump accusing media outlets and law enforcement of having hidden the information from the public before the election.

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It’s a case that will be watched closely as Biden enters office for how he handles the matter. So far he has not announced his pick to head the Justice Department when he takes office in January.

“I’m proud of my son,” Biden said Friday when reporters shouted questions at him about Hunter’s dealings.

Fox News'  Brooke Singman, Thomas Barrabi and The Associated Press contributed to this report.