Labour says it will not support a trade partnership with the United States, Japan and 10 other Pacific nations if new conditions are not met because it worries that it could see New Zealand give up too much power.

Labour leader Andrew Little. Source: 1 NEWS

We will not support an agreement that takes away basic rights for New Zealanders - Labour leader Andrew Little

ONE News can reveal that the Trans-Pacific Partnership Trade deal will stop the right to restrict sales of homes and farm land to non-resident foreigners in fellow TPP countries.

"We will not support an agreement that takes away basic rights for New Zealanders," Labour leader Andrew Little told ONE News.

"This is a big problem we have at the moment we can not have an agreement that cuts across that right to restrict sales."

John Key accepts the TPP deal would block any future restrictions on foreign investment from partnership countries, but not China as it's not signed up.

"This is poltics over principle, I can't believe they'd do this," Mr Key says.

It's also understood that the government would still have the option - under TPP - of using taxes to restrict foreign buyers.

But Labour wants more and has laid down five new conditions that need to be met:

- These include Pharmac being protected.

- That Corporations cannot successfully sue the Government for regulating in the public interest.

- New Zealand maintains the right to restrict sales of farm land and housing to non-resident foreigners.

- That the Treaty of Waitangi is upheld.

- And that there are meaningful gains for farmers in Tariff reductions and market access.

The move comes after a debate in the Labour caucus about what position to take on TPP. There have been splits in the wider Labour movement over the TPP with many in the Unions not wanting to have a bar of it.

One News Political Editor Corin Dann says the key bottom line is likely to be the ability of a future labour government to restrict farm and housing sales to foreigners in future.

Labour has a policy of banning sales of housing to non-residents and its understood the TPP deal would not allow such a ban against other member of the trade pact.

However a government would in future be able to impose taxes to try and restrict land sales.

John Key says Labour is putting politics over prosperity by imposing such bottom lines around things like foreign land sales as the deal opens up trade access to the biggest and four biggest economies in the world.

Earlier this month Labour drew flak for the use of data which it claimed showed that a large number of Chinese foreign buyers were buying up Auckland housing.

The TPP does not include China.