A group of Republican lawmakers demanded documents on Friday from U.S. regulators, voicing concerns that decisions about whether to designate large financial companies as systemically risky are unduly influenced by an international body.

Senior members of the U.S. House of Representatives’ Financial Services Committee said in a letter that they fear the United States may end up surrendering on financial regulatory matters to the Financial Stability Board, a group they referred to as an “international old boys club that deliberates in secret.”

The letter was sent to Treasury Secretary Jack Lew, Federal Reserve Chair Janet Yellen, and Mary Jo White, the chair of the Securities and Exchange Commission.

Lew, Yellen and White are all members of the Financial Stability Oversight Council, a U.S. regulatory body that is charged with policing the market for emerging risks.

The 2010 Dodd-Frank law gave the group the power to dub large financial companies as “systemically” risky if their failure could cascade through the marketplace. Any company deemed systemic is subject to stricter oversight by the Fed.

The FSOC has already given three companies this tag—American International Group Inc, General Electric Co.’s GE Capital and Prudential Financial Inc.

Now, the council is reviewing whether large asset managers such as BlackRock Inc. and Fidelity should be next.

Republicans on Capitol Hill say the FSOC operates in a black box and makes ill-fated and poorly informed decisions that could harm U.S. companies.

They are also worried designation decisions are driven by the Financial Stability Board – an international regulatory arm of the Group of 20 leading economies that is based in Basel, Switzerland.

The Financial Stability Board, which includes Fed Governor Daniel Tarullo as a participating member, has gone ahead of the FSOC with guidelines for systemic designations by its member nations’ regulators.

For instance, the group published proposed criteria for designating mutual funds that, if finalized, would capture 12 to 14 U.S. funds. It sought public comments on the plan and is now weighing whether certain companies should be deemed globally risky.

U.S. regulators do not have to accept the global group’s suggestions of which companies to designate for tougher supervision here. But Republicans say they fear the input sways the decision-making process.

“We have concerns that decisions are being made that could have significant impact on the U.S. economy and its citizens through a non-transparent process by an international body that is not accountable to the American people,” wrote Financial Services Committee Chairman Jeb Hensarling and five other Republicans on the panel.

They asked for copies of all memos and drafts exchanged between U.S. officials and several international groups that are represented on the Financial Stability Board concerning the methods the global group uses to designate companies.

A Treasury spokeswoman said: “We received the letter and will respond in due course.”

(Reporting by Sarah N. Lynch; Editing by Mohammad Zargham)