Some Democratic senators want the U.S. Department of Health and Human Services to warn states not to cut funding for clinics like Planned Parenthood or they will face federal penalties from the government.

A group of 30 senators sent the request in a letter to Secretary Kathleen Sebelius on Thursday.

The letter refers to a law recently passed in Indiana that excludes funding to Planned Parenthood. Other states are considering similar laws.

The senators write that such legislation is "in direct opposition" to congressional intent and contradicts "the spirit and the letter" of existing laws.

Officials with the HHS department did not comment on the letter, but the agency is expected to address the issue soon.