The US Securities and Exchange Commission's staff of 450 is turning to regional American regulators for help as it struggles to enforce registration rules on more than 5,000 hedge funds while overseeing 8,000 mutual funds.

The SEC's deadline for hedge funds with more than $25m (€20.9m) to register is February 1 but only about half the estimated 5,000 funds which qualify to register have done so, according to analysts.