WASHINGTON (AP) -- The Humane Society and a national egg farmer cooperative say they will jointly propose federal legislation that would phase out the use of battery cages for egg-laying hens and establish other treatment standards.

The United Egg Producers and the Humane Society of the United States announced their agreement Thursday.

The proposed bill would phase-out battery cages and gradually require cages that would give many hens more space and allow hens to express natural behaviors. It would also require companies to indicate on carton labels how the hens that produced their eggs were treated.

Industry officials say a national standard would be better than a "patchwork of state laws and regulations."

The Humane Society says the bill would improve the lives of hundreds of millions of hens.