By Patrick Rucker

WASHINGTON (Reuters) - The Federal Reserve will be more open with Wall Street about how it conducts its annual "stress tests" of the largest U.S. banks, the central bank said on Tuesday.

The Fed made the promise at the conclusion of an independent, two-year study of how the central bank examines a few dozen of the largest firms on Wall Street.

Specifically, the Fed promised to be more open about "the qualitative assessment process (and) detailing its reasons for decisions to object to specific firms' capital plans," the central bank said in a letter to the Government Accountability Office.

Banks with more than $50 billion in assets must submit to the Fed review. Among the 33 lenders that must satisfy the Fed each year are firms like JPMorgan Chase & Co <JPM.N>, Goldman Sachs <GS.N> and Wells Fargo & Co <WFC.N>.

Rep. Jeb Hensarling, the chairman of the House Financial Services Committee, said the Fed was too opaque and called for major reforms.

"The GAO report confirms the secrecy surrounding the stress tests makes it almost impossible to measure the effectiveness of the Fed's regulatory oversight or the integrity of the tests' findings," the Texas Republican said in a statement.

Although the GAO findings are non-binding, they could exert some influence on an impending debate about whether financial regulations are unduly costly.

President-elect Donald Trump has said he wants to ease federal regulations.

A copy of the GAO report can be found here: http://www.gao.gov/products/GAO-17-48

(Reporting by Patrick Rucker, Editing by Franklin Paul and Dan Grebler)