The Federal Reserve on Tuesday asked BlackRock to steer tens of billions of dollars in bond purchases, a reflection of the influence of the world’s largest money manager.

BlackRock will purchase agency commercial mortgage-backed securities secured by multifamily-home mortgages on behalf of the New York Federal Reserve. The Fed will determine which securities guaranteed by Fannie Mae, Freddie Mac and Ginnie Mae are suitable for purchase. BlackRock will execute the trades.