The U.S. Senate Banking Committee is clearly concerned about Facebook's new cryptocurrency project and how it is treating individuals' financial information.

The banking committee wrote an open letter to Facebook founder and CEO Mark Zuckerberg Thursday, asking him to share details about its secret cryptocurrency project, with a particular focus on consumer privacy.

"Last year, Facebook asked U.S. banks to share detailed financial information about consumers," the letter says:

In light of these concerns, the committee wants Zuckerberg to outline how the Facebook cryptocurrency, referred to under the codename of "Project Libra," would work; what outreach Facebook has done to financial regulators; and what users can expect in terms of privacy and consumer protection.

More broadly, the committee has asked Facebook to share what consumer financial information has been shared by banks and other financial institutions; what Facebook does with that information (including whether that information is shared or sold to other third parties); whether Facebook has credit rating and other personal information about individuals; and how Facebook avoids violating the Fair Credit Reporting Act.

Little is known about Project Libra. The company quietly began building up a blockchain research team last year, headed up by vice president and former Coinbase board member David Marcus.

The company has posted numerous job listings for the team since, and notable figures in the space such as crypto economist Christian Catalini, a researcher with MIT, have also joined the project.

The company is reportedly looking to raise as much as $1 billion for the project to use as collateral to back a stablecoin.

Mark Zuckerberg image via Frederic Legrand - COMEO / Shutterstock