Citing reports that foreign banks either own or are trying to buy one-ninth of the nation's commercial bank assets, House Banking Committee leaders have began a major investigation of foreign bank operations in the United States.

Rep. Fernand J. St Germain (D-R.I.) chairman of the House Financial Institutions subcommittee, yesterday asked the General Accounting Office to study the invasion by foreign bankers.

St Germain's call for a GAO study came on the heels of a requiest by House Banking Committee Chairman Henry S. Reuss (D-Wis.), who last Thursday called on four other government agencies to study the same question.

The two powerful congressional overseers of the banking industry cited what Reuss called "the rapid takeover, in whole or in part, of U.S. banks by foreign entities." The two questioned not only the purchases of American banks by foreign investors, but also the opening of offices and branches of foreign banks in this country.

Reuss and St Germain at least 47 foreign-owned banks in the U.S. hold assets totaling $19 billion, and foreign investors have proposed acquisition of additional banks with assets of $23 billion more.

The major banks that foreign investors are trying to take over include Marine Midland and National Bank of North America, both in New York; Union Bancorp. of Los Angeles; and Financial General Bankshares of Washington.

"If the announced acquisitions are consumated, foreign banking interests would control about one-ninth of total domestic commercial bank assets in this country through branches, agencies, wholly and partly owned subsidiaries," said Muriel Siebert, New York superintendent of banking, in a letter released by St. Germain and Reuss.

Siebert complained that "our own U.S. banks operate under statutory and regulatory restrictions which place them at a distinct competitive disadvantage relative to their foreign bank competitors."

The New York State bank regulator argued that, "In the bank acquisitions area, U.S. policy clearly favors foreign banks at the expense of domestic banks." She said Amerian banks are prohibited by the federal law from buying banks in other states and are often blocked by antitrust laws from expanding in their home states. Neither restriction hampers foreign banks, Siebert noted.

It is difficult for state banking authorities to oversee foreign-owned banks, Seibert contended, raising the major issue to be studied by the GAO.

St Germain asked the GAO to assess the impact and effectiveness of two recently passed banking measures, the International Banking Act and the Financial Institutions Regulatory Act.

Asking the GAO to report by this summer, St Germain said the agency should analyze the ability of federal bank regulators to supervise foreign bank operations in the U.S., the effectiveness of the supervision of foreign banks, and the impact on U.S. banks and bank customers of foreign bank competition.

Reuss last week asked the Federal Reserve Board, the Comptroller of the Currency, the Feberal Deposit Insurance Corp. and the Treasury Department to comment on the growth of foreign banking.

In another banking development yesterday, the Federal Reserve issued new rules to limit preferential treatment of bank insiders in the wake of disclosures about former budget director Bert Lance's Georgia banking activities. The rules restrick loans to officers, shareholders and companies connected to the bank or its officers.