Prime Minister John Key warned Labour yesterday against pressing for any disclosure of the Endeavour Trust documents of Finance Minister Bill English over his Wellington home.

Responding to calls from Labour's Pete Hodgson to see the trust documents or the minutes of its meetings, Mr Key said:

"I caution the member if he wants to have an open disclosure of every trust document and every superannuation document of every single member of Parliament, it would be a very interesting road to go down."

Mr Key has firmly backed Mr English saying that Mr English had absolutely complied with the legal test required for the allowances he had received.

But Labour hardman Trevor Mallard chipped at Mr English throughout question time yesterday calling him a "money launderer", and "Phillip Field II" and calling on him to resign.

In the light of some papers released under the Official Information Act, Mr Hodgson is attempting to rekindle the issue of Mr English's former ministerial housing arrangements.

The English family home in Wellington is owned by an English family trust, the Endeavour Trust, and Mr English, his general practitioner wife, Mary, and their six children live there.

As an ordinary MP, the trust was getting about $460 a week for the house, the same as other out-of-Wellington MPs.

After Mr English became a minister, the same house was leased by Ministerial Services, and the rent of $700 a week paid to the trust - as well as power and cleaning - and a television was delivered to the property.

Under the rules the increased allowance was possible only if Mr English had no pecuniary interest in the house.

In the 2008 register of MPs' pecuniary interest, Mr English declared that he had a pecuniary interest in the trust. This year's register has no declaration of a beneficial interest.

Mr English has previously said he did not change the arrangements of the trust in order to maximise entitlements and yesterday said that in fact he had never held a beneficial interest.

Mr Hodgson yesterday asked how come, if Mr English had no pecuniary interest, a memo from one of the minister's staff had supplied the back details of the Endeavour Trust to Ministerial Services.

Mr English has since repaid the difference between what he got as a minister and an ordinary out-of-town MP saying it was "not a good look".