The Coalition has followed through on one of its election commitments to seek a reversal of world heritage listing on part of the Tasmanian world heritage wilderness area, despite opposition from environmental advocates, logging groups and the state government.

Tasmanian senator Richard Colbeck, who is parliamentary secretary to the minister for agriculture, announced on Friday that the government will deliver a proposal to the Unesco world heritage committee asking for a “minor boundary modification” which includes the delisting of around 74,000 hectares.

Unesco will give its verdict on the proposal when the world heritage committee meets in June this year. If approved, it would wind back part of the listing of 170,000 hectares which were added to the existing world heritage forest area in early 2012 by then environment minister Tony Burke.

That decision was reached with the support of the timber industry and environmentalists amid a peace deal seeking to end decades of dispute over the forests in the state.

Colbeck said the listed area will still retain “high value tall forests and giant trees in the Weld-Snowy Range, Huon Picton, the Great Western Tiers and the Styx-Tyenna regions”.

“No one thinks Tasmania should plunder its natural resources in the pursuit of short-term gains,” said Colbeck.

“The Coalition’s forestry policy will create a truly sustainable forestry industry for Tasmania, providing dividends for the environment, the community and the industry.”

However the decision has been labelled a “smokescreen” to reopen old-growth forests to logging, despite loggers not wanting it.

“This [area] is over half of the new reserves agreed for protection under the groundbreaking Tasmanian forest agreement,” said Vica Bayley, Tasmania campaign manager for the Wilderness Society.

“Our environment minister is proposing to axe global recognition for these forests when no one in the industry wants this,” Bayley told Guardian Australia.

“This is a purely political stunt aimed at tearing up the goodwill and the good progress that’s been made between hostile adversaries in the forestry debate.”

In December Glenn Walker, national campaigner at the Wilderness Society, told Guardian Australia that there were fewer than 100 hectares of plantation forest within the 170,000 hectare parcel, and the majority of it is old-growth forest.

Tasmanian Greens leader Nick McKim said the government’s decision is designed to “plunge Tasmania back into conflict at the expense of our forests and forest industry”.

“Opening up these magnificent forests for logging is like mining the great pyramids of Egypt for road gravel,” said McKim.

“Just when Tasmania was beginning to move on from the tired old conflicts of the past, the extremist Liberals are trying to drag us back. If the Liberals want to destroy the forest industry and damage Australia’s reputation as a global citizen then they are going about it in the right way.”

Tasmania environment minister Brian Wightman said in December that just seeking to delist a world heritage area would “undoubtedly bring Australia into disrepute”.

“The Tasmanian forest agreement is paving the way for the establishment of a sustainable, long-term and successful forest industry,” he said.

“But the federal and state Liberal parties are hell-bent on taking the industry backwards and removing any chance for Tasmania to market its products.”