ST. PAUL — The operation of Minnesota state government would be restricted to critical functions in a shutdown that’s less than two days away, a judge ruled Wednesday, raising the stakes as Democratic Gov. Mark Dayton and Republican legislative leaders try to strike a budget deal that has eluded them for months.

Ramsey County Chief Judge Kathleen Gearin weighed in from the legal front, with a shutdown due to start at 12:01 a.m. Friday.

Her ruling came as Dayton and top lawmakers were sequestered in the governor’s office on their sixth straight day of budget negotiations. They have yet to report a breakthrough in a drawn-out dispute over the level of spending in the next two-year budget and how to pay for it. Dayton wants to raise income taxes on high earners, while Republicans insist on no new revenue. The talks broke after the ruling was issued and were to resume Wednesday afternoon.

The disagreement has brought Minnesota to the brink of its second government shutdown in six years. Gearin’s ruling made clear that a government closure would be far more extensive than a partial shutdown in 2005.

She largely adopted Dayton’s vision of what would count as critical state services in a shutdown, rejecting a more expansive list proposed by Attorney General Lori Swanson. Gearin ruled that the state’s core functions were “far less in number and breadth” than Swanson’s interpretation.

She found that some programs, such as horse racing and child care aid programs not directly tied into the federal welfare system, were important but did not rise to the level of critical services. She acknowledged that those programs would suffer harm from a shutdown but said her authority was limited by the constitutional separation of powers.

“Neither the good services they provide nor the fact that they may cease to exist without state funding is sufficient cause to deem their funding to be a critical core function of government and to overcome the constitutional mandate in Article XI,” she wrote, referring to nonprofit organizations that weighed in on the case.

Gearin ordered the state to keep paying for critical services, amending Dayton’s list to her ruling with slight adjustments.

She said that state payments to cities, counties and schools would continue, and the Legislature would stay funded “sufficiently to allow them to carry out critical core functions necessary to draft, debate, publish, vote on and enact legislation.” Dayton’s office would operate with a pared-down staff.

Gearin also named former Supreme Court Chief Justice Kathleen Blatz as a referee to rule on unclear areas of funding in a shutdown.

Dayton and lawmakers have been in secretive negotiations for nearly a week with no breakthrough. Dayton said a day earlier that Wednesday would be a critical day if they are to prevent a government shutdown. He has also ruled out calling a special session until he and the Republicans agree on the overall budget.

Republicans are pressing him to call them into special session to pass some parts of the budget and measures to prevent a shutdown. Dayton has said he wouldn’t do that.