Legislation requiring mutual fund companies to clearly detail all fees charged in connection with 401(k) retirement investment plans, was backed by the U.S. House Education and Labor Committee on Wednesday.

The panel vote 29-17 in favor of the measure that would require itemized disclosure of fees including administration fees, transaction fees and charges for investment management.

The legislation, which now goes to the full House, would also mandate that employers offer a low-priced index fund to workers. The bill is opposed by the U.S. Chamber of Commerce, financial institutions and investment advisory companies.

Committee chairman George Miller, a California Democrat, said workers have the right to know "how much Wall Street middlemen siphon off from their savings" through various fees attached to 401(k) plans.

"You can lose 75 percent of your savings in fees if you're not paying attention and you can do it on the recommendation from an investment counsel," Miller told the panel.

The bill would allow the government to impose a $1,000 per day penalty for certain violations.

The legislation also would change pension accounting, lowering the trigger requiring companies with underfunded pensions to report financial and actuarial information to the government.

The panel rejected a handful of amendments that would have lightened the requirements on the funds.

The Investment Company Institute, the mutual fund industry group, complained in a letter on Wednesday that the "disclosure requirements are overly broad and imprecise." It also said the legislation would set a "dangerous precedent" by requiring plans to include at least one index fund investment option.

The fund industry, backed by many Republicans on the committee, said the new mandates amounted to unnecessary government meddling.

"Without government interference, employers across the country have been capable of picking out" investment options, said Representative Tom Price, a Republican on the panel.

In the Senate, Democrat Herb Kohl is working on a similar fee-disclosure bill.