The Federal Government is considering opening up land for farming in northern Australia as part of a deal to export food to China.

A joint study with the Chinese government into the proposal is expected to be released within months.

Trade Minister Craig Emerson says there is no proposal for "buying up the farm".

He says the plan is designed to lift Australian food production for world markets.

Some sites under consideration are the Ord River in Western Australia and the Atherton Tableland in Queensland.

Liberal Senator Bill Heffernan says the plan is an attack on Australia's sovereignty.

Senator Heffernan says there would have to be big changes in the law for the plan to go ahead and it is not the right thing to do.

"I just think we've got to be more emotional, more passionate, this is not xenophobic, there are clear loopholes in the Foreign Takeovers Act and in the Taxation Act and this is a decline in the meaning of sovereignty," he said.