Shares fall below the offer price due to a possible review in Washington.

Market skepticism regarding Elon Musk’s $44 billion acquisition of Twitter Inc. has returned on worries that the transaction may be seized by the government.

Twitter’s stock price dropped 4.9% to $49.89 per share, further deviating from the $54.20 per share offer and widening the arbitrage spread for the deal to its biggest in two weeks.

Twitter shares fell 16% in pre-market trading.

The action was taken in response to a Bloomberg News story that the Biden administration is debating whether the US should scrutinize some of the billionaire’s enterprises for national security reasons, including a relationship with the social networking platform.

The acquisition, which won’t likely be finalized until the end of this year, could be delayed if the Committee on Foreign Investment in the United States, or CFIUS, starts a national security review.

Despite a 16% decline in pre-market trading for Twitter shares, some of the losses were offset when a White House spokeswoman claimed that no such negotiations had taken place.