NEW YORK (

TheStreet

) --

Fannie Mae

and

Freddie Mac

were once again the worst performers of the financial sector Thursday, one day after U.S. regulators instructed the government-sponsored enterprises to delist from the

New York Stock Exchange

.

Fannie and Freddie

shares fell more than 20% after the Federal Housing Finance Agency (FHFA) said Wednesday it has directed both to delist from the NYSE.

The FHFA said the determination to direct delisting is related to stock exchange requirements for maintaining price levels and curing deficiencies, and "does not constitute any reflection on either enterprise's current performance or future direction, nor does delisting imply any other findings or determination on the part of FHFA as regulator or conservator."

Fannie and Freddie expect that the delisting of their common and preferred stock from the NYSE will be effective 10 days after informing the

Securities and Exchange Commission

, which would come on July 8. After delisting from the NYSE, both stocks will move to the over-the-counter market, the companies said.

Video: Housing Hits Market >>

Fannie Mae shares plunged 20.5% to 44.7 cents, bringing the stock's two-day decline to 51.7%. Freddie Mac shares slid 25.1% to 56.4 cents, bringing the stock's two-day drop to 53.7%.

Most U.S. bank stocks were falling as well as the broader

market indices fell 0.7% on weaker-than-expected manufacturing data

.

Wells Fargo

(WFC) - Get Report

was lower by 1.9% to $27.58,

Bank of America

(BAC) - Get Report

slipped 1% to $15.71,

Morgan Stanley

(MS) - Get Report

declined 1% to $25.51,

Citigroup

TST Recommends

(C) - Get Report

was down 0.8% to $3.96,

JPMorgan Chase

(JPM) - Get Report

gave back 0.8% to $38.22, and

Goldman Sachs

(GS) - Get Report

was off 0.4% to $136.58.

Elsewhere, Swiss lawmakers agreed to hand over the names of

4,450 American clients suspected of dodging taxes

through

UBS's

(UBS) - Get Report

private offshore accounts to the American authorities.

The agreement allows Switzerland to meet obligations it had negotiated with the U.S. last August, after an enormous tax case was launched against UBS, alleging that it helped American clients avoid taxes on income totaling up to $20 billion.

UBS shares were up 2% to $14.08 following the news.

Meanwhile, the

Securities and Exchange Commission

has reportedly closed an investigation of

American International Group

(AIG) - Get Report

and some of its executives over the giant insurer's near collapse in 2008.

Citing two sources familiar with the matter,

Reuters

reports that U.S. regulators have ended a probe focusing on AIG Financial Products head Joseph Cassano and others several weeks after the U.S. Department of Justice closed its criminal investigation in May.

AIG shares were lately down 1.1% to $37.47

-- Written by Robert Holmes in Boston

.

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