Sen. Richard Burr, R-N.C., talks with reporters in the Capitol after the impeachment trial of President Donald Trump adjourned for the day on Monday, February 3, 2020.

WASHINGTON — Senate Intelligence Committee Chairman Richard Burr, R-N.C., is facing questions about his decision to sell between $630,000 and $1.7 million worth of stock one week before global financial markets began a historic slide in response to the coronavirus pandemic.

A second Republican senator, Georgia's Kelly Loeffler, also sold large amounts of stock in late January and early February, when U.S. markets were hitting all-time highs.

Both Burr and Loeffler have received non-public information about the global spread of coronavirus from Executive Branch officials, who have been briefing senators regularly since at least January.

In a statement Friday, Burr said his decision to off-load his stock was based "solely on public news reports," including those from CNBC.

"Understanding the assumption many could make in hindsight however, I spoke this morning with the chairman of the Senate Ethics Committee and asked him to open a complete review of the matter with full transparency," Burr said.

Burr TWEET

Members of Congress are prohibited by law from using non-public information they obtain through their official positions in order to personally profit off the stock market.

There is no evidence that either Burr or Loeffler received specific, material, non-public information and then used it to trade specific stocks, which would qualify as insider trading.

On Feb. 13, one week before U.S. stocks began sliding, Burr sold more than half a million dollars worth of shares in a single day. The sales amounted to 33 individual transactions.

A spokeswoman for Burr confirmed the sales to ProPublica, but did not directly address whether Burr's decision to sell was informed by non-public information he received as a senator. CNBC asked her this question directly on Thursday, but she has yet to respond.