Virginia Gov. Bob McDonnell won't rule out altering a bipartisan agreement to expand Medicaid coverage in the state, despite Democrats' insistence that McDonnell had promised not to mess with the deal.

Republicans and Democrats last month moved to set up a special panel of 10 lawmakers to oversee Medicaid reforms and determine whether the state should enroll 400,000 more Virginians in the government-run health care program. That measure is now among the hundreds of bills the General Assembly sent to McDonnell, who has until midnight Monday to act on them.

Democrats sought assurance from McDonnell during the session that he wouldn't tamper with the Medicaid expansion in exchange for support of a transportation funding bill important to McDonnell. The governor wrote a vague letter supportive of the bipartisan compromise that appeased Democrats, and lawmakers left Richmond with a budget and transportation package passed.

But a spokesman for McDonnell's office says the governor doesn't think the letter keeps him from making substantial changes to the Medicaid provision.

McDonnell has insisted the panel does not expand Medicaid without significant reforms, but dismantling it could win over conservatives unhappy with the Republican governor's transportation tax hikes. Attorney General Ken Cuccinelli said late last week that the Medicaid agreement may be unconstitutional.

- Steve Contorno