At a hearing before the U.S. Congress on Thursday, representatives of the stablecoin operator Circle called to crack down on its competitor Tether (USDT). USDT of Tether is by far the largest stablecoin in terms of market capitalization, at USD 97 billion. In second place is Circle's USD Coin (USDC), with about USD 28 billion.

USDC's publisher was referring to U.S. financial services firm Cantor Fitzgerald, which manages Tether's portfolio. According to Caroline Hill, director of regulatory policy at Circle, Cantor made global "terrorism and illegal activities possible," which was "unacceptable."

According to Hill, the U.S. Treasury Department therefore has the authority to take legal action against Tether. She hopes they will "look seriously at this, given Tether's reputation," as well as data that would show "terrorist financing and other harmful activities."

This is not the first time the publisher of stablecoins has been pilloried. Last year, U.S. politicians Cynthia Lummis and French Hill called for criminal charges against the company. Again, the charge was terror financing.

The stablecoin company responded and stated that it was already cooperating with U.S. authorities to prevent such activities.

In a statement Ardoino accused his competitors of "misleading the [U.S.] Congress." It was an "act of desperation."

Meanwhile, another of Tether's partners, Deltec Bank & Trust, is in the spotlight. Bloomberg reports that the bank supported the machinations of collapsed crypto exchange FTX and its failed trading company Alameda Research.

Alameda allegedly obtained unofficial loans in USDT from Deltec and made a profit from them, according to court documents. Deltec representatives believe the allegations are unfounded.

Tether is not named as a defendant in the court documents at this time.