Despite some senators in the United States opposing Meta launching its digital currency products, the development of the social media giant’s digital wallet, Novi, continues apace. 

Stephane Kasriel, head of Meta’s cryptocurrency and fintech unit Novi, officially announced on Wednesday that Meta’s messenger subsidiary, WhatsApp, has started testing transactions through Meta’s Novi wallet.

According to the executive, the new feature is available for a “limited number of people” in the U.S., allowing users to send and receive money on WhatsApp “instantly and with no fees.”

Kasriel noted that Meta has been able to test and learn which features and functionalities are “most important to people” since it introduced the Novi pilot in mid-October. He added that using Novi doesn’t affect the privacy of WhatsApp personal messages and calls, “which are always end-to-end encrypted.”

Will Cathcart, head of WhatsApp at Meta, confirmed the news on Twitter, noting some U.S. users can now send and receive money with Novi on WhatsApp. “People use WA to coordinate sending money to loved ones, and now Novi will help them do that securely, instantly and with no fees,” he wrote.

Formerly known as Facebook, Meta officially launched a digital currency pilot in collaboration with major crypto exchange Coinbase and stablecoin firm Paxos in October. The pilot initially rolled out in the U.S. and Guatemala, using Pax Dollar (USDP), a dollar-pegged stablecoin issued by blockchain trust company Paxos.

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A U.S. nonprofit organization, the Open Markets Institute, subsequently sent a letter to multiple regulators, including the U.S. Department of Justice, arguing that Meta may be “in the illegal business of receiving deposits without a bank charter.” The organization specifically pointed out that USDP is one of the smaller stablecoins “with far less liquidity and usage” than the top stablecoins like Tether (USDT) and USD Coin (USDC).

“There are several legal and regulatory implications for Facebook’s pilot that warrant particular attention by the agencies,” the Open Markets Institute letter stated.