Australian Greens leader Christine Milne's motion to set up an inquiry into the process undertaken leading up to the request to remove about 74,000 hectares of Tasmanian forests was successful yesterday.

The inquiry will look at interactions between the Environment Department and Prime Minister's office and seek more information about the reasons for the request for the minor boundary extension to the World Heritage Committee. 

The establishment of an inquiry follows the passing of a motion condemning the government's decision to try to  have the Tasmanian World Heritage Area reduced. 

Liberal Tasmanian Senator Richard Colbeck said the government would co-operate with the inquiry, but he did not expect it to have an  impact on  the deliberations of the World Heritage Committee.  

``We'll be doing what we see is needed to get the result we want, which we think is a fair one,'' Senator Colbeck said.

The Liberal Party went to the federal election promising to wind back the extension granted last July, a key outcome of the forestry peace agreement.

Senator Colbeck said there was clear evidence that the extension included areas that had been clear-felled, rather than pristine forests. 

If the areas are delisted, Senator Colbeck does not expect them to be logged for some time. 

``We're not saying there's an intention to rush back into those areas,'' he said. 

The Senate also passed a motion calling on the government to rule out allowing a pulp mill to use native wood. 

The inquiry is due to report by May 15.