County councillors in Cumbria say they remain to be convinced that a plan to make the Lake District a World Heritage Site would benefit the area.
The area has been trying for World Heritage status since 1985
The Lake District National Park Authority (LDNPA) has been trying since 1985 to win United Nations approval.
On Thursday Cumbria County Council said it had reservations about the plan, but would defer a final decision on supporting a bid until October.
One councillor called the proposal "airy, fairy, incoherent nonsense".
The LDNPA believes it will cost at least £350,000 to fund an application. Cumbria County Council was being asked to support a donation of about £50,000.
But at the county council meeting in Kendal, Liberal Democrat councillor Stan Collins, who sits on the LDNPA board, said of the bid: "It's not coherent, it's not objective and it's not measurable.
"I don't see what the benefits are for the Lake District and people of Cumbria. But I do see there are going to be a lost of costs ahead if it proceeds."
Tim Stoddard, leader of Cumbria County Council, said it remained unclear how World Heritage Status would benefit Cumbria's environment, economy or services to the community.
He also expressed concerns that the initial cash backing of £50,000 could escalate.
However, he said a county council representative would be attending a final meeting of interested parties dubbed a "make your mind up" at Wray Castle on the banks of Windermere in October.
He said until that meeting the county council had an "open mind".
The LDNPA says World Heritage Status could bring increased international recognition for the Lake District, attract more tourism and help protect traditional farming.
However, it also acknowledges that it is likely to mean unwelcome planning constraints, increased bureaucracy and a negative effect on tourism in neighbouring areas.