Topeka ? Gov. Kathleen Sebelius on Monday vetoed a budget provision that sought to influence Kansas University Medical Center’s affiliation negotiations with a Missouri hospital.

Sebelius said the provision, which had been approved by lawmakers in their final appropriations bill, represented unnecessary interference and micromanaging.

The budget proviso said that KU Medical Center could not enter into any affiliation agreement until it entered into a new operating agreement with KU Hospital. It required both sides to negotiate with each other and exercise “due diligence.”

KU Medical Center has proposed an affiliation with St. Luke’s Hospital of Kansas City, Mo., saying the deal will improve medical research and health care in Kansas and Missouri, and help KUMC attain designation as a national cancer center.

But KU Hospital, which competes with St. Luke’s, has said the affiliation will hurt it, and many lawmakers have said they fear KUMC’s move toward St. Luke’s will reduce the number of physicians in Kansas.

The feud between the medical center and KU Hospital has been boiling all year before the Legislature.

Lawmakers return for the final day of the legislative session on Tuesday and could attempt to override Sebelius’ veto. That would require a two-thirds majority, or 84 votes in the 125 member House, and 27 votes in the 40-member Senate.

Earlier in the session, Sebelius vetoed another budget proviso that would have given KU Hospital final say over any affiliation between KUMC and St. Luke’s. She said the Legislature shouldn’t interfere with the medical center’s negotiations.