WASHINGTON (AP) — Government dairy subsidies that affect the cost of a gallon of milk are set to expire at the end of the year as farm-state lawmakers said Tuesday that they do not expect to have a new farm bill — or an extension of current law — before Jan 1.

Expiration of the current dairy subsidies triggers 1930s and 1940s law, outdated statutes that could upend the commercial dairy market and eventually cause the price of milk to rise. But Senate Agriculture Chairwoman Debbie Stabenow, a Democrat, said she has assurances from the Agriculture Department that the price spikes would not happen before the end of January, and she and House Agriculture Chairman Frank Lucas, a Republican, say they hope to have a final farm bill deal by then.