A water company is appealing against an order requiring it to repair a storm-damaged road.
A section on the western side of Thirlmere reservoir in Cumbria was closed in 2021 amid fears rocks could fall from an overhead crag.
Cumberland Council said it was "disappointed" United Utilities (UU) was contesting the Section 151 order issued by the authority last month.
UU said it "had no choice but to appeal" because the legal timescale of 28 days was not achievable.
The closure of the U7003 has meant walkers, cyclists and horse riders have to use the busy A591 on the eastern side of the lake instead.
Cumberland Council has approved a further closure, to continue after the current notice expires on 11 January, because of an "unacceptably high risk" of rock and tree falls.
But it has "emphasised its commitment" to the road's eventual reopening "once highlighted safety risks at Rough Crag have been addressed".
The road has needed repairs since Storm Arwen in 2021 and the council said UU had responded "positively" to the order it issued in October under the Highways Act 1980.
Executive member Denise Rollo said she was now "extremely disappointed" by the company's appeal.
"This contradicts their statement that they want to work with us to reopen the U7003," she said.
"Following the meeting on Friday, we were able to inform the public that we were making progress; however, our officers will now be spending their time preparing to go to magistrates' court.”
UU said it remained "fully committed" to working with the council to reopen the road as soon as possible.
"Unfortunately, we had no choice but to appeal the council’s legal notice for works to be carried out within 28 days," a spokesperson said.
"This is simply because it is not possible to gain the necessary permissions and complete the work by early next week, which is the legal timescale."
Last week the company said work could not be carried out without permission because the area has protected status, delaying repairs.
Thousands of people have signed a petition calling for the road to be reopened.
The council said it was waiting for a response from the Department for Transport regarding whether horse riders would also be prohibited from using the road.