Institutional money manager State Street Corp faces $22 billion exposure to asset-backed commercial paper conduits, the off-balance sheet vehicles that have caused problems for rivals in recent weeks, British newspaper The Times reported.

The Boston-based bank has credit lines to at least six conduits, which account for 17 percent of its total assets, the paper said, citing regulatory filings.

The conduits are packages of retail and commercial loans financed by short-term debt raised in the commercial paper market, the report said.

Investors have increasingly worried about the conduits amid fears that banks will have to fund the debt from their own balance sheets if these vehicles cannot sell on their maturing paper, the report said.

State Street's percentage makes it the most highly exposed bank to conduits among its European and American peers, the report added.

State Street spokespersons did not immediately return calls for comment.

(Reporting by Lewis Krauskopf, editing by Rory Channing)