Federal Reserve Chairwoman Janet Yellen warned members of Congress against interfering with the central bank's operations Wednesday, saying in testimony prepared for an appearance in the House that new laws limiting the Fed should be avoided.

"[M]easures that affect the ability of policymakers to make decisions about monetary policy free of short-term political pressure, in the name of transparency, should be avoided," Yellen wrote in her legally mandated testimony on monetary policy.

The statement includes a section dedicated to warning of the adverse consequences of various bills that have been considered by congressional Republicans critical of the Fed's accountability and transparency, including an effort to audit the Fed's monetary policy decisions.

Claiming that the Fed already "ranks among the most transparent central banks," Yellen said that "efforts to further increase transparency, no matter how well intentioned, must avoid unintended consequences that could undermine the Federal Reserve's ability to make policy in the long-run best interest of American families and businesses."

Yellen's warning came in the context of testimony that says the outlook for the U.S. economy is "favorable" and that the Fed is likely to raise its short-term interest rate target from zero this year.

The Fed chief is set to appear before the House Financial Services Committee later Wednesday morning. Members of the panel have advanced legislation that would require the Fed to spell out a monetary policy rule and then compare its decisions to that rule, explaining any deviations. Yellen has argued that such transparency measures are not needed.

The hearing likely will involve a number of confrontational questions from lawmakers, many of whom have expressed frustration about the Fed's transparency, its stimulus efforts and its handling of an internal investigation into a leak of its monetary policy plans.