The Greens are criticising the Federal Government for keeping secret a contract with traditional owners about a nuclear waste dump in the Northern Territory.

The Greens asked about an agreement between the Northern Land Council, Muckaty Land Trust and the previous Federal Government in committee hearings yesterday.

Senator Scott Ludlam says it involved an initial payment of $200,000 to a small group of traditional owners.

He says the contract is not being made public and the intentions of the Resources Minister, Martin Ferguson, are clear.

"He intends to coercively dump the nation's most dangerous industrial waste, probably at Muckaty Station in Tennant Creek," he said.

"They've had two years to deal with this situation.

"They're clearly in violation of commitments they made before the election."

The Resources Minister's media advisor says it is the Northern Land Council, not the Government, that wants the agreement kept confidential.