President Bush has vetoed a bill designed to protect doctors from a 10.6% cut in their reimbursement rates when treating Medicare patients. The White House supports rescinding the pay cut, but objects to the way the legislation would finance the plan by reducing spending on private health plans. Lawmakers are under pressure from doctors and the elderly patients they serve to void the rate cut, which kicked in on July 1. As a result, both chambers of Congress are expected to move quickly to try to override the veto.