In a statement late yesterday afternoon, LWP Property Group managing director Danny Murphy said the group was offering to hand over up to 5765hectares of land and to remediate the disused Ayrefield colliery near North Rothbury.

Mr Murphy said the offset offer included $1.1million to help the government manage the land, while remediating the surface facilities of the former underground mine and the adjoining Black Creek would cost more than $5million.

He said the proposed land transfers were part of a voluntary planning agreement.

Such agreements were decided on by the state government as an appropriate way of dealing with environmental offsets after an October 2009 Land and Environment Court decision struck out earlier ‘‘deeds of agreement’’ as ‘‘land bribes’’.

Cessnock Greens councillor James Ryan said last night that the offsets appeared to be the same ones that were offered with Huntlee the first time around under its previous owner, Hardie Holdings.

He said the offset lands were much larger than the development area but the development area was ‘‘high-value valley-floor forest’’, while the offset lands were ‘‘non-threatened mountain bushland’’.

‘‘Regardless of whether the mechanism is the appropriate one or not, what they are doing here is offering a bucketful of rocks in exchange for a handful of diamonds,’’ Cr Ryan said.

Yesterday’s announcement by LWP said the voluntary planning agreement had been put on display by the NSW Department of Planning but a government spokesman said this was not the case.

‘‘The Department of Planning regrets that there has been a delay in placing the draft voluntary planning agreement on the website relating to the proposal for the Huntlee New Town site,’’ the spokesman said.

‘‘Documents are in the final stages of checking.’’