Planning minister Greg Clark emerged from a meeting with the conservation group mounting a furious onslaught on the proposed planning bonfire claiming the Government's objectives are completely compatible with those of the National Trust.
He met Trust chair Dame Fiona Reynolds to discuss the Draft National Planning Policy Framework and described the meeting as useful.
But the Trust refused his suggestion of further discussions on details, saying it was looking for bigger reassurances.
"Mr Clark confirmed that, as it always has been, the role of the planning system continues to ensure that promoting growth is combined with safeguarding our natural and historic environment," said DCLG afterwards.
But Dame Fiona said that the planning system is being turned into a tool for economic growth which it is not designed to be.
"We have formally asked from the highest levels that clarification is given," she said.
"David Cameron and George Osborne are the two leaders of government who could give that reassurance. Until we are reassured on that, it would not be appropriate to discuss in detail the wording of the NPPF."
Downing Street later said Mr Cameron would consider meeting her.
