The Tasmanian senator is trying to raise nearly $240,000 to cover Forestry Tasmania's legal costs from his unsuccessful Federal Court challenge against logging in the Wielangta Forest on the East Coast.

Yesterday, Forestry Tasmania revealed it had earlier offered to settle the matter for $200,000, but that Senator Brown had rejected the offer - instead offering to pay $140,000.

Forestry Tasmania general manager of corporate relations Ken Jeffreys said the counter-offer was unacceptable.

Senator Brown yesterday maintained he was acting on legal advice when he decided to reject Forestry's offer.

"My advice was that even the current amount was too high, but the cost of litigating to get it brought down to where it should be would be as much as the savings that it might have involved," he said.

If Senator Brown does not pay the money by June 29, Forestry Tasmania may begin bankruptcy proceedings against him - which could cost him his seat in the Senate.

"I'm not going to let it (the debt) go beyond there (June 29) if I can help it," Senator Brown said.

He has already secured the support of high-profile entrepreneur Dick Smith, Northern Tasmanian gardening identity Peter Cundall, and Victorian Electrical Trades Union secretary Dean Mighell.

Mr Cundall said yesterday that helping Senator Brown cover the legal costs was a "natural instinct".

Mr Mighell said he would be happy to support Senator Brown - saying the Greens leader "took on a worthy cause".

Senator Brown said any donations above $300 would be declared publicly on the Senate's gifts register.

Prime Minister Kevin Rudd yesterday said he was "quite distressed" to see news of Senator Brown's legal bill.

Federal Environment Minister Peter Garrett said he had "some sympathy for Senator Brown's predicament".

"But at the end of the day, if you are going into the business of taking court action to challenge decisions then you are bound by the decisions that the court makes," Mr Garrett said.

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