Investment company RLJ Western Asset Management LP has raised enough money to join with the government in buying toxic assets held by banks, the Treasury Department said Thursday.

The purchases of the soured mortgage securities and other assets in the government's Public-Private Investment Program, or PPIP, are aimed at enabling banks to resume more robust lending to support an economic recovery.

Treasury said that RLJ Western Asset Management raised more than the $500 million minimum needed to close investment funds under the program. The company is a minority-owned partnership between RLJ Companies LLC _ owned by Robert L. Johnson, founder of the Black Entertainment Television network and owner of the NBA's Charlotte Bobcats _ and Western Asset Management, an affiliate of Baltimore-based investment firm Legg Mason Inc.

RLJ Western joins six other firms or partnerships in the program; the seven have raised a total of $4.09 billion in private-sector capital. Treasury will match that money and provide additional investment capital. The total purchasing power to buy up banks' toxic assets now stands at $16.36 billion, the department said.

The others participating are: Alliance Bernstein LP, BlackRock Inc., Wellington Management Co., Invesco Ltd., TCW Group Inc., and a partnership of Angelo, Gordon & Co. LP and GE Capital Real Estate.

The program has been plagued by delays and some analysts wonder how effective it will be. Others question whether it puts government money at risk while benefiting wealthy private-equity firms.

Treasury initially announced that the program would buy as much as $1 trillion worth of bank assets. The program was scaled back several times as the financial sector stabilized and banks became reluctant to sell the assets at fire-sale prices.

But Treasury remains optimistic about the program and said announcements about the remaining two firms being approved to participate are expected soon.