Yellen will convene the heads of the Securities and Exchange Commission, the Federal Reserve, the Federal Reserve Bank of New York and the Commodity Futures Trading Commission, the Treasury said on Tuesday. Yellen sought and received permission from ethics lawyers before calling the meeting, according to a document seen by Reuters, along with clearance to engage on wide-ranging issues in the financial services industry. Yellen"s decision to seek the waiver followed a report here by Reuters that because of speaking fees she was paid by a key player in the GameStop saga, hedge fund Citadel LLC, she may need permission to deal with matters involving the firm. A Treasury official, who declined to be identified by name, said the meeting would be held this week, possibly as early as Thursday. “Secretary Yellen believes the integrity of markets is important and has asked for a discussion of recent volatility in financial markets and whether recent activities are consistent with investor protection and fair and efficient markets,” Treasury spokeswoman Alexandra LaManna said in a statement to Reuters. ADVERTISEMENT VOLATILITY CONCERNS Yellen’s action comes after days of gyrations in the shares of video-game retailer GameStop, headphone maker Koss Corp, cinema chain AMC Entertainment and other stocks and commodities favored on the Reddit social media site’s Wall Street Bets forum. Retail traders last week bid up the shares to force short-sellers, who profit if a stock falls, to close their positions at massive losses, sending GameStop to a dizzying high of $483. But GameStop crashed back to earth, closing down 60% at $90 on Tuesday, leaving many traders with huge losses. Silver prices also fell. The SEC last week warned here that "extreme stock price volatility has the potential to expose investors to rapid and severe losses and undermine market confidence." Slideshow ( 2 images ) The Federal Reserve Board declined to comment and the SEC, New York Fed and CFTC did not respond to queries about the meeting late on Tuesday. The Treasury official said Yellen was looking for an update from the top U.S. financial regulators. The meeting signals heightened concern about the volatility just a week after Yellen was sworn in as the first female U.S. Treasury secretary. The saga is likely to expedite a regulatory review of the ever-larger role played by non-bank firms in the financial markets, regulatory experts say. One of these is Citadel, which extended hedge fund Melvin Capital a $2.75 billion lifeline last week after the latter firm suffered massive losses in short positions. Yellen earned more than $700,000 in speaking fees from Citadel, as recently as last fall. In an ethics agreement here, she pledged not to involve herself in specific matters involving the firm - as well as major banks including Citigroup, Barclays and Goldman Sachs - without first seeking authorization. ADVERTISEMENT MARKETS, SECTOR CLEARANCE Treasury ethics attorneys have given Yellen flexibility to work on any related markets or broad financial services sector issues, with no limits on current or future matters, the Treasury official said. She may need to seek further authorization to deal with specific firms she listed. In the memo granting Yellen permission to call the meeting of regulators, a Treasury ethics official, Brian Sonfield, said it would be “difficult, if not impossible” for Yellen to recuse herself from matters involving market volatility. “You are the Secretary of the Treasury, the duties of which require you to be involved in a broad array of matters focused on these sectors,” Sonfield wrote. “Issues relating to these sectors could arise at any time without the opportunity for consultation with the ethics office,” and “argue in favor of prior authorization.” Reporting by David Lawder and Trevor Hunnicutt; Additional reporting by Andrea Shalal; Editing by Heather Timmons, Cynthia Osterman, Peter Cooney and Gerry Doyle