"any decision on whether to add a new currency to the Libra reserve will be based on all the facts and circumstances at the time, including any direct or indirect regulatory restrictions," Facebook wrote.
The Facebook and Libra alliance's plan to launch a digital currency is facing a strong backlash from lawmakers and regulators. Unlike Bitcoin and other digital currencies, Libra will be backed by a reserve fund of government-issued currencies and debt instruments.
In response to Warner's written questions, Facebook said it retained the possibility of introducing the digital currency outside the United States, even though regulators in the United States still had doubts.
"We understand that the Libra Union will not provide the digital currency in any jurisdiction until regulatory concerns are fully resolved and properly approved," the company wrote, adding that Facebook will meet U.S. regulatory requirements.