JACKSON HOLE, Wyo (Reuters) – Reforms put in place after the 2007 to 2009 crisis have strengthened the financial system without impeding economic growth, and any future changes should remain modest, Federal Reserve Chair Janet Yellen said Friday in her fullest defense yet of the rules put in place after the Great Recession.

“The balance of research suggests that the core reforms we have put in place have substantially boosted resilience without unduly limiting credit availability or economic growth,” the Fed chair said at an annual central bank research conference.

Some changes to individual regulations may be warranted, Yellen said, specifically mentioning possible relaxation of the Volcker rule limit on banks’ equity trading, and further relaxation of rules that apply to medium-sized and smaller banks. Steps may be needed, she agreed, to improve liquidity in parts of the bond market, though that system remained “robust.”

Overall, the Fed chair said, “any adjustment to the regulatory framework should be modest and preserve the increase in resilience” in a financial system she said is now better able to weather future shocks.

She did not mention monetary policy in her prepared remarks.

But her comments amount to a strong message to Congress and a White House administration that has called for some rules included in the Dodd-Frank law and other regulations to be eased, arguing that they have slowed the economy.

President Donald Trump’s nominee as vice chair of the Fed for regulatory issues, Randal Quarles, has been an advocate of such changes.

Yellen said she and other current Fed members are not averse to revisiting how different regulations are working in practice, “and considering appropriate adjustments.”

But she cautioned against putting the events of a decade ago too far in the rear view mirror.”Already, for some, memories of this experience may be fading – memories of just how costly the financial crisis was,” she told an audience of Fed staff and central bank colleagues from around the world.

The stability of the current system guards against a repeat, she said, while outside analysts have noted that it could also free central bankers to leave interest rates lower instead of worrying about the impact of those low rates on financial markets.

Yellen said that overall, the regulatory change put banks, and the economy, back on their feet.

Post-crisis reforms “resulted in a return of lending growth and profitability among U.S. banks,” she said. “Material adverse effects of capital regulation on broader measures of lending are not readily apparent.”