WASHINGTON — House Republicans are considering a plan to sharply reduce the amount of income American workers can save in tax-deferred retirement accounts as part of a broad effort to rewrite the tax code, according to lobbyists, tax consultants and congressional Democrats.

It is unclear if Republicans will ultimately include a cap on contributions in the tax bill that they are expected to release in the coming weeks. Such a move would almost certainly prompt a vocal backlash from middle-class workers who save heavily in such retirement accounts and from the asset management industry.

The proposals under discussion would potentially cap the annual amount workers can set aside to as low as $2,400 for 401(k) accounts, several lobbyists and consultants said on Friday. Workers may currently put up to $18,000 a year in 401(k) accounts without paying taxes upfront on that money; that figure rises to $24,000 for workers over 50. When workers retire and begin to draw income from those accounts, they pay taxes on the benefits.

Rumors have circulated for months that negotiators were debating including a cap as a way to help offset the revenue loss from a reduction in business tax rates that Republicans have put at the center of their plan. Reducing contribution limits would be, in effect, an accounting maneuver that would create space for tax cuts by collecting tax revenue now instead of in the future.